Pro Ears - Pro Tac SC Gold - Military Grade Hearing Protection and Amplification - NRR 25 - Ear Muffs - Lithium 123a Batteries - Black Military grade dual circuit boards. Gold Connectors for high quality audiophile sound. Automatic shut off.Proform Leather ultra comfortable ears seals. Padded and adjustable headband. Amplifies sound more than 8x normal hearing. Weighs only 10.1 ounces. Fast attack time of 1.5 milliseconds. Includes 2 Lithium batteries. 3.5mm input jacks for i-pod and MP3 players. Battery life is 250 hours. Weighs only 10.1 ounces. Fast attack time of 1.5 milliseconds. Includes 2 Lithium batteries. 3.5mm input jacks for i-pod and MP3 players. Battery life is 250 hours.