The air filters are hard to find in good used shape at a reasonable price. Also some sellers don't seem to know what a good air filter is . I found 1 seller on ebay that had an after market that was actually for an 034 at a reasonable price and bought it. Doesn't seem put together quite as well as oem but with about 15 minutes of cutting I haven't noticed anything getting through. After I try it out longer, if it holds up and is still doing a good job I will probably by more.