Shopping Cart (0) All Categories > Chuck Jaws & Accessories > Square Serrated Master Keys > Item # 21MK All CategoriesAll Categories Chuck Jaws & AccessoriesChuck Jaws & Accessories Square Serrated Master KeysSquare Serrated Master Keys Item # 21MK Item # 21MK, Square Serrated Master Keys 21MKSquare Serrated Master Keys Email This Page Download PDF Download PDF Printable Page List Price $80.00 Qty. Order Close Window Unit of Measure Imperial Metric Both Specifications Chuck Size N/A 21-24 in530-610 mm A Width N/A 1.487 in37.8 mm B Height N/A 0.50 in12.7 mm C Length N/A 2.50 in63.5 mm H Bolt Size N/A 3/8 N Depth N/A 0.13 in3.3 mm O Pitch N/A 0.25 in6.4 mm Material N/A 4140 Steel