The item has been repaired before the tank production for 17/12/57, which cause is contaminated metal scrap (scrap iron, welding), and other impurities in the product tank.
Used tanks were repaired cm before the production date 12/17/57, which causes the contaminated scrap metal. (Scrap) welding and other impurities within the product container.
The packing tank was fixed Sam products on 17 / 12 / 57 which causes a contaminated scrap metal scrap and other impurities (welding) within the container goods.