| Blade Width
Measure near the center of the blade. | 2.25" |
| Blade Thickness
Measure near the center of the blade. | 0.187" |
| Blade Length
Measured diagonally from the corners of the blade | 20-1/2" |
| Outer Hole Diameter
This is the diameter of any holes to the sides of the center hole. | 3/8" |
| Center Hole Size
Many blades will have a round hole in the center of the blade and you will need to know its diameter. Blade Length 5 or 7 Point Star Center holes may be 5 or 7 point star shaped. 5 point star on blade7 point star on blade Square or Rectangular The MTD built blades on many walk behind lawn mowers have a 'bow-tie' hole. In this case the Oregon replacement blade will have a rectangular center hole which will fit on the bow-tie pattern on the blade adapter. Square or Rectangular hole on blade MTD Blades The MTD® built blades (Bolens, Cub Cadet, Troy-bilt, White, Yard Machine, and Yardman) may have a 6 point star. Oregon replacement blades will have a 'Y' shaped center hole which will fit exactly on the 6 point star on the blade spindle. 6 point star for MTD blades The two sizes of the 6 point star. If your blade spindle has a bolt and lock washer that holds the blade to the machine you would use the 11/16" star or 'Y' blade. blade spindle with bolt and lock washer. If your blade is secured with a large flange nut then you would use the 5/8" star or 'Y' blade. blade spindle with large flange nut | 3/8" |
| Center-to-Center
If there are outer holes; this is the distance between the centers of those outer holes. | 3" |
| OffSet
(Sometimes referred to as offset): If you set the blade on a table this is the distance the center of the blade is above the table top (if any) when the cutting edges are flat on the table | 1/2" |
| Air Lift
Air lift is the distance the lift panel rises above the cutting edge. | 13/16" |
