Razor 
Flat, low profile transmitter with a unique blade clip design that deflects objects and protects the transmitter and the tail feather from impacts. Among the strongest transmitters available with an antenna under 7" long and utilizing a single 1632 battery. This is the ultimate tail mount transmitter, designed specifically for tail mounting with long battery life and the highest output power. Crystal less electronics ensure high durability and excellent signal performance. Weight: 7.5 grams. Battery Life: 10 days plus an additional 3 days in low battery mode (over 300 hours total)Range: 30+ miles