SmartStrip is a tool that measures the volume and temperature inside the keg. When applied to the keg wall, it reads remaining beer contents and temperature using liquid crystal technology. Apply to a clean, dry keg. Simply place the SmartStrip with its repositionable adhesive backing on the keg. Activate by spraying with hot water and wiping with a cloth. Current beer level will immediately appear. Temperature reading is always available, no activation necessary. In stock and ready to ship. Features: Easy to apply. Eliminates lifting, shaking or guessing the keg content level. Designed to be reusable; the adhesive backing will hold it securely to the keg for a number of applications. Click photo for details and directions. Specs: Dimensions: 1 1/4"W x 16"H. Compatible Kegs: 1/2, 50 L, 1/4 Slim, 1/6th. Temperature Range: 30F to 50F (-1C to 9C).