The Alpha Communications RCB2100SF Series Refuge Call Boxes are used with the AlphaRefuge 2100 Series Area of Refuge system, and are Flush Mount type. The PWR2410A can provide power for the RCB2100SF series Refuge Call Boxes, which operate on 24VDC 'remote' power (suffix-R). The PWR2410A is not needed when the RCB2100SF series Refuge Call Boxes are powered by 'direct' 120V AC power (suffix-D). The RCB2100SF Series Refuge Call Boxes come standard with a built-in heavy-duty metal call button,and are available with an optional mushroom head call button (add Suffix- M). The RCB2100SF Series Refuge Call Boxes come standard with a built-in back-up battery and charging circuitry and feature a Red call placed / call answered LED.