Pur Black Foam is for outdoor use and will quickly seal cracks, crevices and voids to help prevent insects and other small pests such as mice, rats and birds from getting inside your home. Pur Black is convenient, cost effective and easy to use, not to mention paintable and sandable. This product may be used to fill any void, crack or crevice and wont just deter pests, but it will also stop water, gas, smoke, and more. Pur Black is used by roofers, contractors, wildlife control specialists, and pest control professionals. Application: Pur Black Foam must be applied using a Pageris Foam Gun model GU01 or GU24 (sold separately), or similar type foam gun.