M8-1.25 Metric Acorn Cap Nuts Dome Head Nuts, Stainless Steel 18-8 (304), Plain Finish, 10 PCS: Amazon.com: Industrial & Scientific
600pcs) DIN 1587 M8 Hexagon Domed Cap Nuts, High Type A2 Stainless Steel, Ships Free in USA by Aspen Fasteners, ASSP158728: Amazon.com: Industrial & Scientific
M8 Acorn Nuts (DIN 1587) - Black 18-8 / 304 Stainless Steel: Accu.co.uk: Nuts