3100 Series Reference Masters are offered in 5
sizes to accommodate our No. 2900 series Large Diameter Groove
Recess Gages. They feature a depth range from 0 to 3"
and 7/16" rack & pinion fine adjustment for fast and
easy setting. The range blocks are hardened and precision
ground and the Reference Master body is made from precision
ground and stress relieved alloy steel tubing. tTis
Reference Master may be used with both the No. 2920, 1" diameter
and No. 2930, 1/4" diameter measuring tips supplies for the
2900 series gages.