This Heavy pellet trap is made of 3mm steelplate with 4mm steelplate at the back, making it resistant to high power PCP air rifles.
We have tested this pellet trap ourselves with the Gunpower Texan (677 Joules) at a distance of 10 meters with not even a dent as result!

This pellet trap has a dimension of 23x23cm and has 2 openings at the back for mounting screws.

The trap uses a clamp mount to attach the paper. So any target will fit.