Most states have banned "tube" butyl caulks due to VOC issues. I don't generally advise it, spent many months experimenting with it, and found it's thickness not very suitable for most marine applications. When compressed the lack the elasticity needed to keep a seal just was not there when compared to a premium butyl tape.

The solvents used to give it the consistency come out of the tube make it pretty useless as a "bedding sealant".. Still it is good for some uses but hard to find due to the bans on it in multiple states, which grows each year.. Maine and MA are but two of the states where it is no longer sold...