Steel Grade: ST52/E355 Production Standard : EN 10305 E355+SR /DIN2391 ST52+BKS Inside Diameter Tolerance: H7 - H9 Inside Surface Finish: Ra 0.3 Micron, or better. Straightness between 0.2-0.3mm/meter. ID: 30-1200mm. WT: 3-100mm. Both ends capped and oiled in bundle, suitable for shipment