① The blade is tempered, black coating prevents rust.

② The blade is polished on a one by one basis by hand and is tested on leather sheets, to make sure that it cuts very well.
We ship the tools putting oil on to the blades so as to prevent rust and cover it with a vinyl tube to protect it.

For instructions on how to sharpen the blade, please see the Instagram video and website under the banner of Usage and Maintenance.
If you can’t sharpen the blade well, you can use our “Resharpen blade business”.
(“Resharpen blade business” is mentioned in OKA FACTORY’s 4 commitments)