M6 Nylon Insert Lock Nut Nyloc Type - Galvanised Steel DIN985 These are tapped oversized threads to allow for galvanised layer on male thread d = 11.05 mm h = 6 mm m = 4 mm s = 10 mm thread pitch = 1 mm Nylon insert can be various colours (Usually black / Dark blue). Please ask if colour is important to you DIN985