Ordering new rubber rings using old rings as a guide is sometimes impossible due to broken, non-elastic, or missing rings. The following chart will help you determine the correct sizes for all your rings. Get a piece of string and wrap it around the posts where the rubber would normally be. Mark that spot on the string when it meets back up together. Measure the circumference around the posts (the length of the string where you marked it off. Find that size along the left side and note where that size intersects the red line. Follow that point down. That is the size of your new rubber ring that will fit. These numbers are the inside diameter of new rubber rings, which is how sizes are denoted. Note that small sizes smaller than 1" may be difficult to determine on the chart, but are easy once you know the rules.

Most single playfield posts take 5/16"
Bally mushroom bumpers take 7/16"
Two normal playfield posts nearly touching will take 3/4"
2" flipper will take one 1"
3" flippers take 1/2" x 1-1/2" flipper rubbers (Standard)
3" Gottlieb flippers can take 1/2", but have a better fit with the 3/8" x 1-1/2" flipper rubbers
Don't forget to get a new plunger tip

For example if you have three posts for one rubber and the circumference around the three is 15.0", then you need a new 3.5" rubber ring.

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