About this item 7.2 Volt 1100 mAh battery back up for the Lynx Plus Panel and GSM module for backup power with a 2 pin connector Made up of (6) AAX1100mAh nickel-metal hydride batteries Dimension: 4.72 x 4.09 x 0.71 inches Compatible with the following alarms: WALYNX-RCHB-SC, WALYNX-RCHB-HC, LYNX, C8-B33, MS104, WALYNXRCHB, WALYNX-RCHB-SC, K5109, 781410403291, 55026089, LYNXRCHKIT-SC Compatible with the following alarms: LYNXR-I, LYNXR-2, L3000 LYNX Plus, L5000/5100 LYNX Touch Dimensions: 4.72 x 4.09 x 0.71 inches