The B-3V1A-1P battery is made specifically for High Tech Power Pet MS-4
ultrasonic transmitter collars. Long-life lithium cell powers a collar for up to 3 months. Designed specifically to prevent damage if accidentally installed incorrectly. Has a shelf life of several years. Shipped directly from manufacturer.
B-3V1A-1P Lithium battery for High Tech Power Pet MS-4 and MS-5 Ultrasonic Transmitter Collars
To replace the MS-4 battery
Insert screwdriver or knife in end slot and pry open. Separate top from bottom. Replace battery top with the metal ring visible. Carefully mate top and bottom while keeping aluminum speaker centered in the top hole. Squeeze together the top and bottom until both ends snap.
To replace the MS-5 battery
Unscrew the bottom cover. Pry bottom from top on ends and on edges using small flat blade screwdriver. Remove bottom, note battery orientation. Remove and replace B3V1A battery. With new battery installed, close case. Squeeze until bottom is flush with top. Insert screw and tighten.