Magnetic base; 1-5/8 in. W x 1-7/8 in. D x 1-15/16 in. H; flexible upright; 3/8 in. Diameter x 3 in. Lg rod with 5/16, 1/4 and 7/32 in. Steps; snug with 3/8 in. Diameter hole for gripping indicator stem and 5/32 in. Diameter hole for scriber; push button on-off switch for magnet; grips curved or flat surfaces