Replaces water bottle cap, Bottle will glow when light is turned on, Built-in clip for hanging, Fits most national brand water bottles with standard neck size, Powered by 2 lithium button cell batteries, inserted. Complies with FDA, Prop 65. 2.5" H x 1.25" Diameter. Price includes a 1 Colour Imprint. Imprint area is 0.5" W x 0.5" H on Either Side. Call for multi-colour or multi-location imprints or for rush delivery availability.