These universal snugs (sometimes called sleeves) provide a convenient means of attaching scribers and test indicator shanks to surface gages. These snugs will fit all Starrett® 57 and 257 surface gages and all test indicator clamps and tool post holders.

Starrett® Universal Snug, For Use With: 257 Surface Gages and 196M Universal Dial Indicator, 1-37/64 in L x 1-51/64 in W

• With spindle hole diameters 1/4 in, 5/16 in and 3/8 in and gripping hole diameters range from 3/32 - 1/4 in
• Snug is an advanced new style that is less expensive and more versatile, having the capability of accepting three different spindles or post diameters
• Right direction
• Snugs must be used with the proper indicator holder
• Snugs permit the use of all NO 196, 564, 650, 651, 708, 709, 711 and 811 test indicators
• It will also handle an unlimited number of shank diameters between 3/32 and 1/4 in used on holders with smaller clamp hole

• https://externalassets.unilogcorp.com/ASSETS/DOCUMENTS/ITEMS/EN/Starrett_58S_Catalog.pdf https://externalassets.unilogcorp.com/ASSETS/DOCUMENTS/ITEMS/EN/Starrett_58S_Catalog.pdf