Dogtra Gold 2 Dog 1/2 Mile Remote Trainer 202NCP

Unless you like the rheostat control for levels be wary of this unit.

I feel it's too easy to bump the dial and change the level by accident though

it is somewhat stiff. I much prefer the Dogtra 282 which also has a rheostat

but a digital readout of the level.

Other than that it's a fine unit and the continuous adjustment will allow you to

get the exact level you are looking for.