10.9 Hexagon Trimmer Sems I-3 Black Oxide Film

This product uses SCM hex bolts and 40–50 HRC spring washers.
Spring washers/rounds with embedded metal and S55C circular washers
These washer insert sizes are designed to prevent forgotten washer insertion and decrease time and effort. They are inserted into conventional iron washers. The inner diameter is therefore smaller than the nominal diameter.
This new product is optimal for use in parts that lack strength.