XHT blades are made from the highest grade of steel for the best cutting and performance money can buy. With the best hardness, strength, and durability in the market, this range of blades is recommended for every mower in the market. They are stronger, harder, and last longer in any environment. XHT BLADES Extreme Hardness Toughness Replacement XHT Lawnmower blade. XHT(Xtreme Hardness & Toughness) blades are 25-40% harder than standard lawnmower blades. Benefits of the HXT blade are sharper and longer lasting cutting edges. More resistance to bending. Tighter tolerances in the aftermarket vs. OEM. XHT blades also offer greater impact toughness. By the way they are made in the USA!This sale is for 3 replacement XHT blades. HEAVY DUTY 3" WIDE not the 2-1/2" wide like others on eBay. This is the true blade for the JD mowers. (3) blades needed for 48" cuts. ***Center Hole: 29/32" Width: 3" Thickness: .197" Length: 17" John Deere (UNDEFINED): SEVERAL (48") John Deere RIDING MOWER: F687 (48") John Deere RIDING MOWER: 647 (48") John Deere RIDING MOWER: 647A (48") John Deere RIDING MOWER: 657A (48") John Deere RIDING MOWER: 667A (48") John Deere RIDING MOWER: 717 (48") John Deere RIDING MOWER: 717A (48") John Deere RIDING MOWER: 727 (48") John Deere RIDING MOWER: 727A (48") John Deere WALK-BEHIND: 7G18 (48") John Deere WALK-BEHIND: 7H17 (48") John Deere WALK-BEHIND: 7H19 (48") John Deere ZERO-TURN: Z645 (48") John Deere ZERO-TURN: Z810A (48") John Deere ZERO-TURN: Z820A (48") John Deere ZERO-TURN: Z830A (48") John Deere ZERO-TURN: Z840A (48") John Deere ZERO-TURN: Z850A (48") John Deere ZERO-TURN: Z910A (48") John Deere ZERO-TURN: Z920A (48") John Deere ZERO-TURN: Z925A (48") John Deere ZERO-TURN: Z930A (48") John Deere ZERO-TURN: Z950A (48") John Deere ZERO-TURN: Z960A (48") John Deere ZERO-TURN: Z970A (48") · Disclaimer: We list model numbers and part numbers for references only. At times the same model may take different parts based on serial number breaks or manufacturers specifications. We list all the specifications on the part (size, width, length, thickness, etc.) and YOU must know what is needed on YOUR application. We can’t possibly make it more known as to what you are receiving when you purchase.