AC Fans /DC Fans /Blowers /WireFanGuards /PlasticFanGuards /FanPowerCords /FanFilters Wire Form Fan Guards Back Part Number: TWG-150 For use with fan size Rib Material Dia. Ring Material Dia. Mounting Hole Centers (M/C) Outside Ring Dia (OD) mm in mm in mm in mm in mm in 150 6 2.31 .091 1.80 .071 161.9 6.38 154.4 6.08