Ø5-28mm Chromed 45# Steel Round Bar Hardened Rod Rail Linear Shaft Optical Axis Product Information: Name: hard plated shaft Surface hardness: 50-55 degrees Material: 45# steel Surface finish: 0.3-0.5 Straightness: 0.15/1000mm Plating thickness: 0.02-0.03 The optical axis is the whole (2 meters or 3 meters) clamped between the two ends of the electroplating, so the top two ends may have the electroplating layer is too thin, black and so on.
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