Yookidoo Spin 'N' Sort Water Gear (Wholesale)From colorful spinning machine gears in various shapes to a numbered test tube with holder, this set has everything your soon to be STEM lover needs to get experimental in the bathtub. Encourage color and shape recognition by identifying them as you play together. The gears can be played with water from the tub, so water level and temperature stay constant. No batteries needed and no more running water! This toy promotes STEM learning important to