Left hand lawn mower blade replaces Walker blade 5705-4 for Walker Grass Handling System, G.H.S. 42" cut rear discharge Walker. 15-3445 similar to Stens 355-032, Oregon 91-912. This is the Left hand blade. All lawn mower blades are sold individually. Order a mixed quantity of (1) WA22L & (1) WA22R for 42" cut. Refer to your manual to match blade OEM#s and quantity needed for your deck.