1)No.040 pad ink ,refill Ink for stamp pad 2)Water based ink ,without oil 3)40ml per bottle,OEM order is welcome 4)ASTM D423 1)No.040 pad ink ,refill Ink for stamp pad2)Water based ink ,without oil3)40ml per bottle,OEM order is welcome4)ASTM D4236 certificate5) colors available: red, black, blue, violet, green, yellow....