We've all seen products that were created "just because the engineers could" and not necessarily because they should. The SDR-Beep is a serious piece of engineering that will matter most to those it was designed for, Upland Hunters. Unlike any other product in the category, this remote beeper does not depend on a training collar to operate. You can use your transmitter to operate the remote beeper by itself, the training collar by itself, or both together if you need them. This is a flexible training/hunting accessory that will fit your style. If you own a SportDOG UplandHunter™ 1850, the 1850 transmitter will operate all SDR-BEEP training collar and beeper functions remotely and allow you to run a second dog. If you own a SportDOG SD-1800, SD-2000CAMO, or SD-2500 system, your transmitter will operate the SDR-Beep training collar and the remote locate or "call" function on the beeper. SportDOG Brand®, Gear the way you'd design it.