[Stainless steel material] Made of high-quality stainless steel with chrome plating, undergoing high-temperature quenching treatment for high hardness and durability. Wear-resistant, rust-proof, with good resilience and toughness. Features a smooth surface and precise construction for reliable performance. The stainless steel pressure gauge is coated with anti-rust oil to ensure a long service life. [Excellent design] 360-degree rotating design allows easy unfolding, folding, and portability. Each blade is clearly marked with specifications for quick identification. Includes a blade protector with thumb notch for convenient and safe use. [One machine with multiple functions] Radius gauges accurately measure internal and external radii. Threaded blades of various sizes measure thread pitch. Convex patterns detect concave arcs, and concave templates detect convex arcs. [Wide application] Commonly used to verify the size of drill bits, screws, fasteners, valves, bearings, and other components. Helps identify suitable replacements. Ideal for checking tool angles when cutting threads on a metal lathe and for accurately measuring internal and external threads using various thread pitch blades. Material: Stainless steel Color: Silver Package Contents: 1 x R0.3-1.5 Radius Gauge 1 x R1-6.5 Radius Gauge 1 x R7-14.5 Radius Gauge 1 x R15-25 Radius Gauge 1 x R26-80 Radius Gauge 1 x Feeler Gauge Only the above package content is included; other items are not. Note: Lighting and display differences may cause slight variations in color between the image and the actual item. Measurement error allowance is +/- 1-3 cm.