Fast 50- 50 Flux and Soldernon-Acid:, Premium grade of flux and solder combination, Combines virgin 50/50 finely powdered solder with LA-CO Regular Flux Paste, Non-acid, contains no zinc chloride, Clean, leaves no black residue to obscure the soldering oPeration, Do not use on potable water systems, Physical Form: Paste or Gel, Specific Gravity: 3, 2800, Color: Gray, Usage: Soldering, Quantity: 24 Per case, SKU: ORSNO63534