Selling unit is 4 caps.

These American made caps are used as replacements for many of the common gel and water flasks on the market.
This will fit the gel flasks sold by Ultimate Directions®, Lava belt, TNi and Fuelbelt®, which have a diameter of 33mm (1.3") measured on the outside of the threads.

We also sell complete gel flasks with this cap if you check our other listings. We don't carry the dust caps which go over these caps, but they can be found in many triathlon shops.

Size: 1.4" wide x 1.2" high (35x30 mm), weight for all four is about .72 oz. (20 gm.), shipping weight is 3 oz. (doesn't include any flask)