Applied for No. 657AA magnetic base indicator holder, Nos. 657-1 and -2 Series Magnetic Base Universal Indicator Holder with triple-jointed arm and fine-adjustment
Two 1/4 Inch (6.3 mm) diameter mounting holes
Knurled thumb screw provides secure grip when making adjustments
Snug adapts Starlet 196, 650, and 651 series dial test indicators and 657Y indicator attachment (not included) for use with the Starlet 657X rod