Linear RE - 2SS Residential Telephone Entry System<div style="text-align: left;"><strong>[Product Information]</strong><ul><li id="replacementPartsFitmentBullet" class="aok-hidden" data-doesntfitmessage="We're not sure this item fits your " data-fitsmessage="This fits your "><span class="a-list-item"><span id="replacementPartsFitmentBulletInner"><a href="#" class="a-link-normal hsx-rpp-fitment-focus">Enter your model number</a>to make sure this fits.</span></span></li><li><span class="a-list-item"> Supports 100 entry codes and 100 block-coded transmitters </span></li><li><span class="a-list-item"> Backup battery ready </span></li><li><span class="a-list-item"> Applications include single residence， commercial sites， employee parking </span></li><li><span class="a-list-item"> Simple to program and maintain through on board keypad， touchtone telephone， or computer with modem </span></li><li><span class="a-list-item"> 10.0" W x 6.25" H x 4.4" D </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/31MspucgUeL.jpg" noproxy>