Don't let a worn lawn mower blade spacer keep your lawn looking ragged — restore mower performance with a part engineered for outdoor service. Verified for Ryobi RY40104. Cross-references factory part number 526920001. Common signs the worn part is past its service life: tearing instead of cutting, chipped teeth, or out-of-balance vibration. Manufactured to factory-equipment dimensions and tolerances so fitment is true the first time — no shimming, no filing, no adapters. Installation is straightforward: cross-check the part number stamped on your old unit, mount the replacement in the same orientation, and torque hardware to manufacturer spec. Take pictures before disassembly if it helps with reassembly. Keep your equipment running through another full season of work without the wait and cost of factory replacement. Bolt-in replacement with no fabrication or modifications needed — everything you need for a clean swap.