Gears + oil = a mess. Gears + water = hours of bath time fun. COGS suction to the bath walls and spin when water is poured over them. Positioned just right, they work like a fine-tuned (though not well-oiled) machine. Use Boon COGS with Boon PIPES Bath Toys for maximum fun. These tub toys will have the waterworks on tap - and don't worry, we mean the good kind. Gear heads unite!