John Deere OEM Replacement Blade 330-393
FITS MODELS: Sabre and ZTrak F620 front mounts; Requires 3 for 54'' deck; mulching blade 
Length 18 5/8'' (473.1mm)
Centre Hole 13/16'' (20.6mm)
Width 2 1/2'' (63.5mm)
Thickness ,203'' (5.2mm)