The Internet Pinball Serial Number Database or IPSND collects serial numbers of pinball machines and publishes a database of these on the Internet. Our goal is to make available a registration of all pinball machines in existence and allow tools for slicing, dicing and visualization of the data.

Games: 6,696  Serials: 68,535  Visitors: 74,412,032  Members: 5,634  Photos: 44,048  Lat/Lng: 37,598  Masks: 68,535(1,023.52%)  Traits: 572  Nudges: 223,451  Backglasses: 1,865
  Most Serials: Twilight Zone(1,307)  Most Submissions: Dennis Braun(6,104)  Most Points: Dennis Braun(45,438)  Highest Quality: The Knight(17.00)  Most Nudges: pinballservice-nl(28,311)
Comet - IPSND/IPDB No. 548 - June 1985
Backglass Image
Manufacturer: Williams Electronic Games, Inc., a subsidiary of WMS Inc.
Players: 4
MPU: Williams System 9
Production Run: 8,100
Game Type: Solid State Electronic (SS)
Model: 540
Submissions: 250 serials of 8,100 (3.09%)
Coverage help:

Coverage is a mathematical interpretation of the serial numbers that have been submitted so far. The term 'coverage' relates to the amount of the production run that has been 'covered' in the given submissions.

There are two coverage methods shown, each has a different approach of calculating an guess on the number of games produced by analysing the currently submitted serial numbers.

Linear: Linear coverage simply looks at the highest serial number and subtracts from it the smallest serial number to estimate the number of games produced. For some games, this works fine because the serial numbers were sequential and without gaps (Early Bally, Early Stern, etc). However, this approach starts to fail quickly for games that serial numbers are part of a bigger numbering scheme (Williams pre 1984, Current Stern) or that intentially had gaps/skips in the numbering sequence(Gottlieb post 1960). If you see a linear coverage number that is higher than the known production run, it is probably not the best way to look at the serial range and you should look at the clustered approach below.

Clustered: Clustered coverage assumes that there are gaps/skips in the serial sequence for a game. It groups the serial numbers together based upon how close they are to the next serial number in the sequence. If they fall within a certain threshold then the SerialBot assumes that there are valid serial numbers between the two. If they are far enough apart, then the SerialBot assumes this is a gap. Once all the gaps and groups are determined, it sums up all the linear ranges in each group. This way, if a sample run of games started at 15,000-15,100 and the production games started at 17,000 onwards, it would assume that the serial numbers between 15,100-17,000 were a gap an are not counted. Using this method, as more serial numbers are submitted the gap analysis will get more accurate.

9,103 (112.38%) linear / 7,481(92.36%) in 3 clusters 405 wide.
Cluster Serial Number SerialBot Submitted By Country Game Part

Submit a new Game Trait

The following traits help

Game Traits are properties for an individual game that you would like to see tracked along with the other information gathered for a serial number submission. Some examples of existing traits are... Joust: Black or Blue bottom Arch, Black Knight: Faceted Inserts or Normal Inserts, Twilight Zone: 3rd Magnet Installed or not.

have been submitted for this game...

Field NameDescriptonSubmitted BySubmit DateSubmitted
"COMET" under coin door The word "COMET" is screened underneath the coin door in yellow Pinball Pete5/23/200950

Cluster Serial Number Country

This section lists any known game part serials that happen to match this game's serial mask (if defined). What this can tell you is if a game has any orphaned parts that might exist in other machines. This generally applies to CPU/MPU boards, Driver Boards, Display boards etc that are easily moved from game to game. Repair shops and distributors often robbed parts from other 'scrap' games laying around in a pinch if they were not able to fix the original part or of the original part was damaged beyond repair. If serials start showing up in the database as 'game parts', there is potentially a good chance that that game has been parted out completely, which is unfortunate. It is becoming more and more common for people to part out games and sell them on ebay simply because the seller can often make more money that way.... Please do not sacrifice complete games for money!!!

SerialBotSerial NumberTypeSubmitted ByCountryDetails
36167 54066140 Sound Board Pinball Pete United States flag United States
62311 54067062 Flipper Board Dennis Braun United States flag United States
66567 54067851 Display/Driver Dennis Braun United States flag United States
36310 54067937 MPU/CPU Pinball Pete United States flag United States
42490 54067966 Display/Driver Rod McLarge Canada flag Canada
38039 54067990 Sound Board Pinball Pete United States flag United States
20476 54068260 Flipper Board John Vorwerk United States flag United States
12218 54068348 Display/Driver Jess Askey United States flag United States
64939 54068387 Display/Driver Dennis Braun United States flag United States
49334 54068413 Flipper Board Dennis Braun United States flag United States
37932 54068413 Sound Board Rod McLarge United States flag United States
65132 54068520 Display/Driver Dennis Braun United States flag United States
28080 54068588 Flipper Board Pistol Pete United States flag United States
20477 54068595 Flipper Board John Vorwerk United States flag United States
16565 54068609 Sound Board Pinball Pete United States flag United States
67988 54068718 Sound Board Mark Hoffman United States flag United States
47996 54068800 Display/Driver Dennis Braun United States flag United States
71103 54068883 Display/Driver Jon Scaptura United States flag United States
43075 54068995 MPU/CPU Pinball Pete United States flag United States
76105 54068997 MPU/CPU Dennis Braun United States flag United States
43073 54069026 Display/Driver Pinball Pete United States flag United States
61011 54069165 Flipper Board Dennis Braun United States flag United States
48006 54069251 MPU/CPU Rod McLarge United States flag United States
47949 54069251 MPU/CPU Dennis Braun United States flag United States
68524 54069342 Display/Driver Dennis Braun United States flag United States
32774 54069353 Sound Board Rod McLarge United States flag United States
78364 54069367 Display/Driver Larry Le Feuvre United States flag United States
10922 54069411 MPU/CPU John Duchi United States flag United States
80056 54069452 MPU/CPU Dennis Braun United States flag United States
56934 54069540 MPU/CPU Fun House United States flag United States
78363 54069632 Display/Driver Larry Le Feuvre United States flag United States
20298 54069642 Display/Driver Pinball Pete United States flag United States
62575 54069653 Display/Driver Dennis Braun United States flag United States
48537 54069762 Display/Driver Rod McLarge United States flag United States
48468 54069762 Display/Driver Pinball Pete United States flag United States
22144 54069767 Other/Unknown John Vorwerk United States flag United States
27797 54069782 Display/Driver Pistol Pete United States flag United States
27815 54069790 Display/Driver Pistol Pete United States flag United States
64419 54071031 Display/Driver Dennis Braun United States flag United States
68285 54071107 Sound Board Dennis Braun United States flag United States
57686 54071115 Display/Driver Dennis Braun United States flag United States
63523 54071274 MPU/CPU Dennis Braun United States flag United States
66568 54071322 Display/Driver Dennis Braun United States flag United States
66836 54071342 MPU/CPU Dennis Braun United States flag United States
33865 54071478 Flipper Board Rod McLarge United States flag United States
42841 54071597 MPU/CPU Rod McLarge United States flag United States
51311 54071788 Display/Driver Dennis Braun United States flag United States
63060 54071875 Sound Board Dennis Braun United States flag United States
63054 54071875 Sound Board Dennis Braun United States flag United States
65595 54071919 Display/Driver Dennis Braun United States flag United States
63572 54071932 Display/Driver Dennis Braun United States flag United States
48538 54072343 Display/Driver Rod McLarge United States flag United States
48469 54072343 Display/Driver Pinball Pete United States flag United States
56627 54072345 Display/Driver Rod McLarge United States flag United States
54557 54072362 MPU/CPU Dennis Braun United States flag United States
47273 54072363 Sound Board Rod McLarge United States flag United States
43497 54072363 Sound Board Pinball Pete United States flag United States
56650 54072438 Other/Unknown Fun House United States flag United States
28635 54072452 MPU/CPU Jim Smith United States flag United States
43074 54072745 Sound Board Pinball Pete United States flag United States
61577 54073043 Display/Driver Dennis Braun United States flag United States
78384 54073161 MPU/CPU Dennis Braun United States flag United States
10810 54073204 Power Supply John Duchi United States flag United States
25175 54073725 Sound Board John Vorwerk United States flag United States
32109 54073755 Display/Driver Rod McLarge United States flag United States
43575 54073829 Sound Board Pinball Pete United States flag United States
49418 54073997 Display/Driver Dennis Braun United States flag United States
62212 54074000 Display/Driver Dennis Braun United States flag United States
68284 54074008 Coin Door Dennis Braun United States flag United States
47230 54074897 Display/Driver Rod McLarge United States flag United States
61649 54075097 MPU/CPU Dennis Braun United States flag United States
42054 540I66655 Other/Unknown Antti Peltonen Hungary flag Hungary
53381 540I66864 Other/Unknown Antti Peltonen Hungary flag Hungary
38052 540I66864 Other/Unknown Antti Peltonen Hungary flag Hungary
47679 540I67616 Display/Driver Antti Peltonen Hungary flag Hungary
49439 540I73492 MPU/CPU Fun House Germany flag Germany
62507 540I74310 Display/Driver Dennis Braun United States flag United States

This section lists any known information about how to physically find serial numbers on games created by this manufacturer. For all manufacturer tips, please visit the Serial Tips Page . (Please do not post serial numbers here on this form.)

Posted 1/11/2007 11:54:45 PM by Bill Ung

Newer Williams and Williams/Bally games have cute little stickers everywhere. This began with System 9 games (as far as I know) and include game ID number information, as well as the serial number. There are two styles:

  • The blue/grey and white stickers ran through the Hurricane era. These include the official game ID number (ie: 541 or 50018), separated from the actual serial number by a few spaces. Early games, till about the end of 1986, had five-digit serial numbers. Since then, serial number have always been six digits.
  • The white stickers include encoded game ID numbers. Well, the ID numbers aren't identical to the one you'll find in the ROM, but it DOES match the game ID number listed on the back of the machine. The number may change based on country. This is an item still being debated somewhat.

Overall, you'll find these stickers on the fronts of the cabinets, on top of the head, on the back of the cabinet (along with an encoded manufacturing date), insi

Posted 4/28/2008 2:40:04 PM by Jim West
Pinball2000 machines have two parts each with their own serial number. The base serial number is for the playfield cabinet. This serial number is for the top unit of the pinball.
Posted 12/20/2008 10:07:35 PM by MARK SPENCER
OPEN COIN DOOR, LOOK TO RIGHT , MFG STICKER SHOULD BE ON SIDE.
Posted 2/23/2009 9:24:15 PM by Richard Harvey
Game Date Stamp for BK2K under backbox with head down.
Members can submit new tips on how to find serial numbers! Sign up for a free membership here!

This game has the following serial number formats defined in the database. As serial numbers are sumbitted, trends are recognized and defined or information about a serial number format is collected through historical information.

TypeExamplesRegExMaskLowerLimitUpperLimitAutoAssignable
Production Game 54023080, 54067090, 54067901 ^(540)(?<sortdata>[0-9][0-9][0-9][0-9][0-9])$ True
International Game 540I74577, 540I74484 ^(540)(I)(?<sortdata>[0-9][0-9][0-9][0-9][0-9])$ True
Experimental Game 540X74484 ^(540)(X)(?<sortdata>[0-9][0-9][0-9][0-9][0-9])$ True


The Serial Bot Summary information here gives a detailed explanation of the Serial Bot analysis for this specific game. The theory behind the Serial Bot is this...

Every game has many many serial number submissions, the goal of the IPSND is not to guarantee that *all* information is 100% correct but that over time, the system should automatically devalue inaccurate submissions while increasing the value of correct submissions.

You may click on the SerialBot score of any submission to see how it was calculated.

SerialBot Color Codes:
- Not Validated The serial number submission has not yet been validated by the submitter via email.
- Unknown There is no known information on the serial number format for this game yet. As more submissions are received we can start to make a best guess on the serial number format.
- Good If a serial does not fail any of the tests for a status of Warning or Bad, then it is good.
- Suspect A serial will have a suspect status if the format is technically correct but there is something wrong with the data. Examples might be that the number might be too high or low for the known range of serials for this game.
- Bad If a game has a serial number definition mask defined for it, then a serial may be marked as 'bad' if the number does not validate agains the mask. Masks are created for games by looking at known serial number formats and consist of a regular expression to define the format of a game serial.

SerialBot Scores:
1 Point Awarded if the serial number has a game assigned to it. This autoatically makes submissions with a known game more valuable than submissions without a known game.
1 Point Awarded if the serial number has been 'verified' by the submitter. A submission is 'verifed' if the submitter clicks on the link in the email sent to them for each submission. The basis for this rule is that submissions by people that do not take the time to respond to the email might be entering garbage data and/or giving fake email addresses. However, it is common for 'verification' emails to get stuck in spam filters etc, so, members may have 'verification' emails re-sent at any time.
1 Point Awarded if the submitted serial number matches one of the predefined serial number masks for this game.
1 Point Awarded if the serial number was marked as 'Physically Viewed' during the submission process. This is an interesting distinction as there are many times that serial numbers are submitted off owners lists, Ebay auction, etc. While these serial numbers are valuable, they may also be innacurate. In comparison, Physically Viewed serial number submissions are numbers that the submitter has actually been in front of the machine reading the number and then submitting it. Since it is more likely to get a good visual from a physically viewed machine, this gains an extra point.
1 Point If a photo is uploaded with the serial number submission. The submission automatically gains an additional point. Be aware however that this opens the submission up to 'Nudges' by members where even more points can be added or subtracted based upon the quality and accuracy of the photo.
-3 to +3 Points Members can 'Nudge' every sumitted photo once and give it an extra boost of 1 point or take away 1 point depending if the photo matches the submitted serial number. While any number of members may nudge a serial, the nudging can only affect the score by +/- 3 points in either direction.

The following map shows the locations of all serial numbers that were submitted with a geolocation...