Mr Muscle Shower Shine - 500ml Mr Muscle® Shower Shine is a daily shower spray that helps to prevent the build up of limescale, soap scum and grime. If used daily, the shower should never need to be scrubbed again. Safe for use on most non-wooden surfaces in the shower area, including fibreglass, porcelain, chrome, tiles, glass, plastics, acrylics and shower curtains.