N-21 is included when buying a NM-11/21 . It is used when changing skate blades to remove tube rivets , to attach copper rivets and tube rivets . Copper rivets are removed by cutting them apart with cutting pliers
This hook together with tool set N-21 can be used on the belt buckles of ski boots for processing tube rivets . It can also be used together with tool 28 and tool 29 for larger rivets Uoint rivets with a size up to 025 mm) located on the sides of ski boots.