Chainsaw Chain, 81 Drive Link C-Loop, Fits Stihl Models, 20-In. Coolers but all Pen knives have

but all Pen knives have in common two blades on opposing ends

Unit adds in forward motion and subtracts in backward motion

Wire comes on a reel with a handle and payoff guide

Built-in safety switch to help prevent the water heater from overheating

Chainsaw Chain, 81 Drive Link C-Loop, Fits Stihl Models, 20-In. Coolers but all Pen knives haveOregon, 20", replacement, 81 drive link c loop saw chain, fits stihl #'s: 024, 024 super, 026, 028, 028 super, 029, 030, 031, 032, 034, 034 super, 036, trouble free, cuts every type of timber, stands up in any kind of weather & stays together in all cutting conditions, stays sharper longer, easy to resharpen, has lubrication, sharpening, low vibration & low kickback features, chain meets ansi standards, ul classified.