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How to caulk
Use silicone caulk if you need a neutral-colored waterproof sealant.
There are two main types of caulk-silicone and acrylic latex. Silicone caulk is a completely waterproof and flexible sealant.
It will bond with a lot of different kinds of surfaces. Silicone is a good choice if you're caulking outdoors, or wet indoor spots like around shower stalls and bathtubs.