All steel with gloss white powder coat. Outside nubs for caps on 6 & 8-lug wheels measure 11 5/8". Additional 5 & 6-lug options for this wheel are available on our Hot Rod tab. Some wheel backspaces require reverse rim and are noted with an R in the part number. Our 8x170 bolt pattern options are designed to fit Ford Super Duty F-Series, 1999-2004, and 2005-2016. Please see technical specs on bottom of page for the corresponding part number and year. There are no custom backspace available on 2005-2016 wheels.Lug nuts not included. Please check proper fitment before mounting.