I use and have used 2 different ones , both from lowes or HD . inside DAP 3.0 clear outside DAP Dynaflex 230. Depending on the color you want you can get the Dynaflex in Almond and white. This is a very easy to use, clean up and to me a superior product to a lot of the
I carry this every where I go. You would be surprised how many people come up with LEAKS at the worst times, and if you can help them out it is good.
Oh and when you are caulking, run your point towards the seal it makes for a smoother bead, and as always keep a bowl of soapy water to put your finger in to run over the bead. Works great!!!
Cheers and happy fixing.