This nifty composite tool rolls a structure into the base of Nordic skis.
Rollers allow for more stucture pattern options than a rilling tool.

A simple tool for imparting a structure to the base of Nordic skis. As you roll the composite body along the base of the ski a brass roller presses a structure into the base material. Guide wings integrated into the body of the tool ensure a straight structure. As a ski travels across snow a thin layer of water is formed as the result of friction, the warmer the snow the more water is formed. A structure (basically fancy micro-grooves in a ski base of various patterns) breaks up the surface tension of the water, which can cause drag, and gives that water somewhere to go. The structure impressed by this tool is not permanent but will disappear after the next hot waxing.

Tool includes a plastic hard case and the following 3 rollers
1.0mm G – Universal roller.
2.0mm G – For transformed snow and wet conditions.
0.5mm V – Broken V structure for very cold conditions.