Q. I need to know what is measuring equipment to measure Ra?Zaki Yamani Ahmadengineer - Kuantan, Pahang, MalaysiaOctober 11, 2008publicly reply to Zaki Yamani AhmadProfilometer: Mahr Pocket-Surf on eBay or Amazon (affil links) A. Hi Zaki. You would use a profilometer. Regards, Ted ...