Key-Chain/Wrist-Strap/Carabiner Digital Counter is designed for ease-of-use and fail-safe counting. Features include display count to 99,999, two year constant use battery, water-resistant O-ring-sealed with shock-resistant ABS plastic case, button click for count confirmation, and recessed “no accident” reset. Eliminates gear and miscount problems associated with mechanical counters. Diameter is 1.9 inches by 0.5 inch.