2BLOK™ makes a 100% air tight seal on caulking tubes and foam can applicator straws. I don’t know of ANY other product that can stop a can of Great Stuff™  from hardening in the straw, but mine does! This product is totally unique and comes in packs of 2, which can be used multiple times. I have tubes that are over 2 years old in my basement that are still as fresh as the day I opened them.There is no clean up at all as with the other products that are on the market.

The Power of 2BLOK