We were first introduced to the NOK Training Knife by Tom Sotis from the AMOK System - and we have not turned back since. In our classes as well as in our own personal training, this is what we use.
The Nok Training Blade has a wood center surrounded by a foam padding with a wire type handle wrap. With this training blade you can go very hard with minimal to no chance of injury. You will earn your bumps and bruises and walk away safe as well.
Great for learning safely or going hard and sparing. We go full speed with these blades and have no reservations using them. They are not too good for use as a "marking blade" - but one of the best we have come accross. You will like this and enjoy it the first time you use it.