Great 4 AA battery holder for your Arduino project! Provides 6V output when used Alkaline batteries, 4.8V when used with rechargeable AA. These AA battery holders feature a standard snap connector on one end. The case is made from ABS plastic with nickel plated springs to hold your AA batteries in place. Each battery holder measures 4.375" x 1" x 0.675"( L * W * H ). AA batteries in these holders will last much longer than a standard 9V battery will when powering up electronic projects. AA batteries not included. Ideal for use as a replacement battery holder in the Garrett GTA, GTAx, GTX, GTP and GTI Series metal detectors.