Merry Mac PTO Chipper/Shredder - 3 1/2in. Capacity, Model# TPH-122M Requires 540 RPM PTO speed Requires 10 HP minimum and 30 HP maximum PSC Tractor-mount unit chips 3 1/2 in. thick dry or green logs at 10+ FPM Shredder uses hammermill action to handle all yard and garden