Manufacturer YIXISI. Drilling material: HSS. Shank type Hex. Size: 2.8 × 8 mm, 3.0 × 8 mm, 3.2 × 8 mm, 3.5 × 8 mm, 4.0 × 8 mm. High Quality: Made of high quality alloy steel, with higher precision, higher hardness, faster cutting speed and strong force than ordinary drill bits.
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