Dogtra has designed an electronic collar with large breeds, such as retrievers, and particularly stubborn dogs in mind. The Surestim 7100H can deliver stimulation ranging in one-digit increments from 0 up to 127. An LCD screen on the transmitter shows the exact level of stimulation, even in low-light conditions.

Stimulation can be delivered in momentary nicks or constant streams. A vibration in the transmitter lets the handler know stimulation is being delivered. One transmitter is capable of operating two collars from up to a half-mile away.

Contact: Dogtra; (888) 811-9111; dogtra.com