... use are NAK80, P20, 4140, S50C4. We have 15years experience in making rubber moulds, especially for rubber molds of electronic rubber ... -2weeks, complicated rubber molds like cold runner injection rubber molds in 30days.9. WSR can help customer to run mass production ... reach ±3 shore A tolerance Color: for rubber, usually black, for silicone, can be in any color as you want Machine type: 50 ...