Review on Rectorseal 66345 Metacaulk Rated Sticks by Jared Winebrenner

Useful for sealing floor openings to create a fire barrier and prevent pests from entering the building. (This product will not stop rats/mice as they are likely to be able to burrow through it but it will work on insects.) The putty can be reapplied which is recommended over a fire seal if you ever move or need to do future work on one opening . /pipe you seal. These sticks can be used to form leaves of any shape, but you'll end up using more putty than just one leaf. However, with any fire retardant material, thickness matters and the thicker the barrier (within reasonable limits), the more fire resistant it is.