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Special Series

Grand Logarithmic Grit Chart

Knife Sharpeners and Stone Formats Compatibility Chart

Venev Celectial Family


Venev 4" x 1" Hydra Series Diamond (please read description)


FEPA Grit (Binder, Diamond Concentration)
diamond concentration is better for toothy edge and high performance,
diamond concentration is better for polish and scratch removal.
is nonabrasive binder for fine and ultra-fine grits,
is wear-resistant binder for coarse grits.


Hydra Series is sold "as is", is non-returnable and non-refundable. Please take attention to the description.

Hydra is the name of old KME format diamonds discontinued due to issues with compatibility and flatness. KME owners can switch to the upcoming Scorpion series (retail price 29-49 USD) or purchase very inexpensive Hydra diamonds as DIY and rework. Hydra also can be used as a pocket diamond.

Hydra Series Diamonds consist of 2 mm-thick diamond-bearing layers on the aluminum plate. Extra aluminum blank is included. You can glue it to the diamond to increase thickness and improve compatibility. Flattening the working surface is highly recommended.

Non-OCB only.

The price is 15 USD on 01/01/2020 and will go down for 1$/week until sold out. 


  • Product size: 100 x 25 x 5 mm (4" x 1")
  • Abrasive: Synthetic Diamonds with phenol-formaldehyde bonding
  • Extra: Aluminum blank 102 x 25 x 3 mm
  • Flatness tolerance: Up to 0.6 mm

Questions and answers

If you have a question regarding this product, please feel free to ask.