Diamond lapping plate for flattening and restoring all types of whetstones. Double-sided electrodeposited diamond whetstone for surface restoration. Strong diamond surface restores dented or worn out / curved whetstone surface immediately. Quick surface restoration for coarse and fine finishing whetstones, even very hard ones or ones that easily get clogged. Use the coarse #150 Diamond side to flatten the whetstone surface quickly. Then, polish with the #500 Diamond side to get an ideal whetstone surface instantly. Apply water on the whetstone before using the lapping plate. The plastic storage case can be also used as a holder.