This items guard edges for double bevel knives.

This item cannot guard single bevel knives, for example, Yanagiba,Sashimi, Deba, boning Knives. 

S size:　Western & Japanese Style Petty / Utility Knives  0-150mm

M size:　Western Style Knives 150-170mm / Japanese Style Knives 150-165mm

L size:　 Western & Japanese Style Knives 210-240mm

XL size: Western & Japanese Style Knives 270mm