Hi Dear, carbon steel with nickel plating,or zink coating llips flat head countersunk head self tapping screw M5x45 or 4.8 x45 sample order of 100 kg is required supplier must be delivered this package in yiwu please quote the best sample order price with delivery time and product specification price must be in Kgs and also the unit price Thanks for your response. With Best Regards Nasif Ahmad Engineering Enterprises