Oregon Part Number 183PXLBA074 (Previously 183SLBA074). 18" Oregon Chainsaw Guide Bar Fits Stihl MS241, MS250 & MS251 Chainsaws, using a 0.325" pitch, 1.6mm (0.063"), 68 drive link chain. Requires a 68 Drive link, 0.325" Pitch, 1.6mm (0.063") gauge Oregon Type 22 chain.
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