I never use these saws and plan to put on local c-list. The 026 is not a PRO has base gasket delete, all original OEM but had to shave about .005" off the outer crown of the piston----comp. is around 205psi. Bar on 026 is 16" 3/8" pitch. The 036 PRO has a new Meteor piston with base gasket delete is around 165psi. Bar is 20" 3/8" pitch, chain is pretty well used up.