MH5ACP-34 Bushing / Slide for Wiedemann (R) Workholder OEM Orininal Style - New Style for Models A-30 thru A-60 , S-40 , W-20 , W-30 , W-45 . This is a inch dimensioned part with 1/2 inch pivot hole for the back pivot pins on a MH4APA or a MH4RPA or a MH4APA-T Pivot Arm .