M16 Nylon insert lock nut Nyloc type - Galvanised Steel DIN985 These are tapped oversized threads to allow for galvanised layer on male thread d = 26.75 mm h = 16 mm m = 10.5 mm s = 24 mm thread pitch = 2.0 mm Nylon insert can be various colours (Usually Black / Dark blue). Please ask if colour is important to you DIN985