ExMark OEM Replacement Blade 355-343
FITS MODELS: Lazer Z and Ultra Cut 
Requires 3 for 60'' deck; notched hi-lift blade 
Length 20 1/2'' (520.7mm)
Centre Hole 15/16'' (23.8mm)
Width 2 1/2'' (63.5mm)
Thickness .250'' (6.4mm)