indelible ink for election

1)indelible ink ,different colors ,for election,round bottle
2)with sliver nitrate,can't be washed by water
3)stay for about 25 days.when the ink tipped on the finger ,turn to dark grey color

4)the silver nitrate contending can be required by customer.

5)enough experence in election,export the ink for Iraq,Tanzania,Afghanistan,Nigeria,sudan