About the product:
The experimental instrument plug can be used to block the glass mouth, pipe mouth, fish tank mouth, and so on.

Good choice for you:
Made of Silicone, not easy to deform, has moderate hardness, high elasticity, good insulation and sealing performance, high-temperature resistance, acid and alkali resistance, and is insoluble and non-swelling in acidic liquids.

Specification:
Fit for the hole: 13-17mm / 0.51" - 0.67"
Bottom Diameter(small-end): 13mm / 0.51"
Top Diameter(big-end): 17mm / 0.66"
Body Height: 24mm / 0.94"
In the package of: 15 Pack x Stopper

Easy to install:
Easy to install and widely available, just plug it into the mouth of the object you need to seal.

Tips:
Please ensure the correct size you need before purchasing.