Hengshui Jrain Frp fiberglass stair tread

Center drill bits typically come in two main types - the No. 0 and No. 1 sizes, with the No. 0 being smaller and more suited for starting holes for tapping threads, while the No. 1 is larger and ideal for creating centers for lathe work. They have a distinctive conical shape, with a 60-degree included angle that allows them to create a V-shaped indentation, guiding the larger drill bit or lathe cutting tool into perfect alignment.

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