657AA Magnetic Base Indica tor Holder For use with all Starrett Test, Back-Plunger, AGD, Dial and Miniature-Dial Indicators. Also accommodates similar indicators of other manufacturers. A. 657P Magnetic Base. 1-15/16 x 1-5/8 x 1-7/8" (50 x 40 x 48mm). Push-button on/off switch for one-hand operation. Base has three precision ground magnetic contact points. Grips horizontally, vertically, and upside down. V-step holds base to arbors, shafts, etc. Base has extra 1/4-20 tapped hole on one side for mounting post. Black wrinkle finish on non-working surfaces. B. 657G Upright Base Post. 3/8" (9.5mm) diameter x 7-7/16" (190mm) length overall. 57S and 58S Universal Snugs may also be used. C. 657S Snug. Two 1/4" (6.3mm) diameter holes. Adapts 196, 650, and 651 Dial Indicators and 657Y Indicator Attachment to 657X Rod. D. 657X Rod. 1/4" (6.3mm) diameter x 6" (150mm) long. Accommodates Starrett 708, 709, 811 and 711F Dial Test Indicators and 657S Sleeve. E. 657Y Indicator Attachment. 1/4" (6.3mm) O.D. one end, other end threaded and fits lug backs of all AGD indicators (81, 25, 655, 656) and 80 Miniature Indicators. F. PT18724 Snug. 3/8" (9.5mm) diameter post hole. 1/4" (6.3mm) diameter gripping hole accommodates 657X Rod. 657AA with 711FS Last Word® Dial Test Indicator 657AA with 196B1 Universal Dial Indicator 657Y with lug-on-center back Indica tor Holders C D E F B A 657AA Magnetic Base Indicator Holder - Individual Components Photo Key Cat. No. EDP Description A 657P 52757 Magnetic Base Only B 657G 52753 7-7/16" Upright Base Post Only C 657S 52759 Snug withTwo 1/4" (6.3 mm) Holes D 657X 52764 Rod E 657Y 52765 Indicator Attachment F PT18724 50710 Snug Complete – 1/4" and 3/8" Holes 657AA Magnetic Base Indicator Holder - Complete Set Cat. No. EDP Description 657AA 52743 Magnetic Base with All Attachments – A, B, C, D, E, F 657-650Z 65259 Base and Post Assembly with 650B1 Indicator, 657S Snug, and 3 Contact Points 177 starrett.com I ndica tors and G ages