1. Accuracy Unmatched In MeasurementEmploying a spring mechanism for seamless expansion and contraction, this telescopic gauge set provides an exact fit inside the bore, facilitating precise measurement of its inner diameter. Ideal for machinists assessing dimensions of holes, slots, and recesses. 2. Ease of UseDesigned for straightforward operation, this gauge set allows for efficient measuring by expanding the t shaped part inside the intended hole, followed by size determination with a micrometer or caliper. 3. Comprehensive 6 Piece Gauge CollectionThis set includes 6 telescopic gauges catering to a wide range of diameters: 5/16'1/2', 1/2'3/4', 3/4'1 1/4', 1 1/4'2 1/8', 2 1/8'3 1/2', and 3 1/2'6', covering the spectrum of your measuring needs. 4. Exceptional CraftsmanshipFeaturing tool steel points meticulously ground to precise radii and a knurled handle for a non slip grip, this gauge set combines functionality with comfort in usage.