/ Precision Measuring Tools / Precision Hand Tools / Indicators & Gages / Indicator Accessories / 58S * Not actual product image 56613 58S Universal Snug 56613 Other similar products With spindle hole diameters 1/4", 5/16", 3/8" (6.3, 8, 9.5mm). Gripping hole diameters range from 3/32-1/4"used on holders with smaller clamp hole. Contact Starrett