HORIZONTAL SHAFT IMPACTOR Model 4250 Spec Sheet 38" (.97 m) 92" ( m) 50" ( m) 87" ( m) SHAFT – SAE4150 steel shaft BEARINGS – Selfaligning spherical roller bearing (180mm) ROTOR – 3 bar solid rotor design 96" ( m) PRIMARY APRON – Fabricated 4" Hardox abrasive resistant steel – Adjustable for gradation control – Replaceable wear tips SECONDARY APRON – .