Input Drive Size: 1/2" Drive Shape: Square Length: 35mm Type: Impact Bit Holder Output Size: 1/4" Opening: For 1/4H Bit Product Dimension (Refer Line Drawing Image): D1 Size: 11mm D2 Size: 25mm L Size: 35mm 1/2 Sq. Dr. Adaptor 1/4 For 1/4H Bit Length 35mm