BrassCraft provides a complete line of quality professional plumbing tools at a competitive price. All products have been reviewed and tested by a third party testing lab. In addition, BrassCraft's internal testing facilities have inspected and tested all products in the program for durability, function ability and product longevity. This Shower Valve Socket Wrench Set is used to remove and install shower and tub fittings and nuts. The set made of plated steel contains two-sided wrenches sizing from 21/32 in. to 1-7/16 in.