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Adapta-Capô Size Guide

See the chart below to determine the correct Adapta-Capô needed for your bottle. The neck size is measured in millimeters (mm) from the outside edges of the threads.

Adapta-Cap Neck Measurement

Neck Size

18 mm

20 mm

22 mm

24 mm

28 mm

33 mm

Cap Size

A

B

C

D

E, F*

H

*Size F is for a longer-neck bottle.

You can do this either by measuring the top of the bottle with a ruler or tape measure that is marked in millimeters, or, if you don't have either, you can compare the neck to regular U.S. coins to determine the size.

To measure with a ruler, first take the camp off of your bottle to expose the bottle's threads. Second, measure the distance between the outside of the threads on the opposite sides (shown above).

If you are using a US coin to determine the bottle's neck size, first, remove the cap from your bottle to expose the threads. Second, line up one edge of a coin with one of the outer edges of the threads on your bottle. Third, use the chart below to help determine what size the neck is on your bottle.

Adapta-Cap Comparison Chart

  • A (18 mm): A dime lined up with one outer edge of the threads will reach to the opposite edge of the threads on a bottle with an 18 mm sized neck.
  • B (20 mm): A penny lined up with one outer edge of the threads will almost reach to the opposite edge of the threads on a bottle with a 20 mm sized neck.
  • C (22 mm): A nickel lined up with one outer edge of the threads will reach to the opposite edge of the threads on a bottle with a 22 mm sized neck.
  • D (24 mm): A quarter lined up with one outer edge of the threads will reach just past the opposite edge of the threads on a bottle with a 24 mm sized neck.
  • E (28 mm): A quarter lined up with one outer edge of the threads will reach just past the inside edge of the opening on a bottle with a 28 mm sized neck.