- Built-in repeater receives and retransmits clock sync signal- 915 928 MHz frequency hopping technology- Internal antenna- Built-in diagnostic mode for easy maintenance- 5 yr battery life (standard) or 8 yr battery life (economy)- Black ABS case and polycarbonate crystal- Optional double mount housing available (see CL-DMA16)- Battery Life: 5 years (normal mode), 8 years (economy mode) using (2) Duracell Procell D Batteries (not included). Note: standard alkaline batteries can be used but will have a slig