DMR Wingbar MK4 Handlebars Our DMR Alloy Mk4 Wingbar shouts a graphics refresh on the successful Mk3 Alloy MTB Wingbar but retains all its proven specification. Made from heat treated 7075 alloy, this mountain bike handlebar is light, stiff and strong.This DMR alloy Wingbar's shape was developed with our team riders and Olly Wilkins in particular.