The Armac RKS System is the most economical way to convert your old style planer block that uses the re-sharpenable 3 x 30mm blades to quickly replaceable turnover knives. Just order 2,3 or 4 of the length you require and you get the blade carrier, blade and setting pins. Once the pins have been set, each time you replace a knife, it fits to the pre-set position every time. See overleaf for replacement blades.