Letter 9842, "Ra surface finish vs. grit conversion chart", suggests that a USA grit size of 240 is equivalent to an Ra of about 0.45 µm, while a UK grit size of 240 is equivalent to an Ra of about 1.5 µm. But with this as background, I think you'd better ask your cus...
Prospective, international, multi-centre, randomised (1:1) trial to evaluate the clinical impact of percutaneous transluminal renal artery stenting (PTRAS) on the impaired renal function measured by the estimated glomerular filtration rate (eGFR) in patients with haemodynamically significant atherosclerotic...