A silicon caulking gun is a tool that holds a tube or cartridge thats filled with material used for sealing up gaps and cracks in the home. Caulk can be made of silicone or latex, and is used to bond a wide range of materials like metal, glass, wood and ceramic. Caulk usually comes in a tube. People need a caulking gun to get the caulk out of the tube. The gun is used in the application of caulk. This silicon caulking gun is very similar to a cake decorators gun, showing that he might have gotten his inspiration from the kitchen.