Helps prevent water spots and stains, soap scum and other residue from bonding to:

Shower Glass
Shower linings (tiles, acrylic, fibreglass, etc)
Glass windows on vehicles, buildings/homes, boats, and other equipment
Glass balustrades
Stainless steel railngs, balustrades, sinks and other fixtures
Ceramic and porcelain tiles, sinks and bathroom fixtures
Chrome tapware and fittings
Other hard surfaces.