Small PCB tungsten steel (tungsten carbide) drill bits are ultra-precision micro-tools designed for high-speed drilling on printed circuit boards, typically featuring a standard 1/8-inch (3.175 mm) shank and cutting diameters ranging from an extremely fine 0.1 mm up to 3.175 mm.

Material: Made of solid tungsten carbide (tungsten steel), offering extreme hardness, high wear resistance, and minimal deflection compared to high-speed steel.
Dimensions: Standard overall length is roughly 38 mm (1.5 inches), with a uniform 3.175 mm shank fitting most CNC rotary tools and micro-drills. 
Sizes Available: Commonly sold in graded sets (e.g., 0.1 mm–1.0 mm, 0.3 mm–1.2 mm) or individual packs (like 0.5 mm or 1.0 mm).
Common Uses: PCB circuit board production, CNC engraving, jewelry making, precision plastic machining, and clearing small 3D printer nozzles.

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