I payed $29.98 for one a few years ago with the Bushnell name on it.
It's the long POS with the different cal adapters you stick in the end
of your barrel.Turn it on aimed at a wall and set your scope cross hairs to it.
Sapost to get you on paper.
The ones that fit the chamber are sapost to work better I hear.
I woulden't trust mine to get me on paper at 50 yards unless my targets were 20"x30".