The best shower sealants will be contained in tubes labelled ‘Kitchen & Bath’ or ‘Tub & Tile’.
As that fact would suggest, these types of caulks or sealants will also be effective for bathroom basins and bathtubs, as well as shower enclosures.
Typically, the sealants consist of silicone compounds or acrylic latex, modified chemically to combat damp, and instead attach to smooth surface areas.