A Practical Guide for Restaurants, Commercial Kitchens and the Modern Home KitchenSometimes referred to as a glass rinser or glass washer, a kitchen sink cup washer is a small appliance that is used to swiftly rinse out the inside of cups, glasses, bottles and similar drinkware. Instead than trying to spray a faucet into a container, the user merely inserts the hole above the rinser and pushes down, producing several water jets.But are kitchen sink cup washers really worth the dough?The answer can be yes but only if the equipment is suitable for high use kitchens, cafes, bars and hospitality operations. A cup washer is a dedicated rinsing instrument, not a substitute for a dishwasher, sink faucet or comprehensive cleaning process.