1.Process punch is needed before forming, countersink hole's depth is adjusted by regulating precess punch hole's diameter.

2.The countersink molding insert corresponds exclusively to the thickness of panel. It is not allowed to process panels of different thickness.

3.Material around countersink hole will extruded after molding and slight distortion will appears.

4.It needs special insert design for molding of a bigger plane extrusion and special extrusion.

5.Min sheet thickness of Countersink process must bigger than 1.0mm（t≥1.0mm）.