M10 Nylon insert lock nut Nyloc type - Galvanised Steel DIN985 These are tapped oversized threads to allow for galvanised layer on male thread d = 18.9 mm h = 10 mm m = 6.5 mm s = 17 mm thread pitch = 1.5 mm Nylon insert can be various colours (Usually Black / Dark Blue). Please ask if colour is important to you DIN985