Sharpen in the field, straight off the ute battery. The G1212 Grind-N-Joint is a 24,000rpm, fan-cooled 12V grinder that sharpens any size or brand of chain: change the stone to suit the pitch, set the height gauge, and work along the chain.

Direct drive, so there's no belt to wear out. It comes with a 1/4in stone for lowering depth gauges and a stick of Kool Grind to keep the stone cool and clean. Sharpening stones for your chain are sold separately: see Granberg Grinding Stones.