The special design allows you to get perfectly stable joins. The very high quality steel along with the special silicon (lubricant effect for a smoother penetration) selected from many years of experience, make A+ wedges the best choice in terms of quality available on the market.
Wood Hardness Guide
Soft = Thailand and South-East Asian Wood, Bass, Banak, Obeche, Cellular and Polystyrene
Medium = Cedar, Cherry, Oak, Ramin, Poplar, Maple, Pine, PVC
Hard = Oak, Ash , Hickory, Pecan, Maple, Cherry, MDF and HDF