This gadget is used to adjust the accelerator pump piston in a carburetor. An example has been seen, labeled "CARTER" with "BURE" in small letters between the R and T, plus "Made in U.S.A." and "Assembly No. T109-117S", and, on the opposite side, "Patent 2207396". The Carter T109-117S Universal Pump Stroke Gauge superseded all previous models of Carter pump stroke gauges.