This tools is to make holes on leather using electric screwdriver
There are 2 types :

• 1.0 - 4mm : hole = 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | 4mm
• 4.5 - 8mm : hole = 4.5 | 5 | 5.5 | 6 | 6.5 | 7 | 8mm