Detachable ï¬at form in two sizes. Used with replaceable scalpel blades. Made of stainless steel. Without blades. Slip lock design. Handle No. 3 : For ï¬ner dissections. Used with #10, 11, 12 and 15 scalpel blades. Length 130mm. Handle No. 4 : For heavier dissections. Used with #20, 21, 22 and 23 scalpel blades. Length 130mm.