IAPMO Listed solder and water soluble flux NSF-61. Flux meets ASTM B-813 standard and is City of L.A. approved. Lead free silver solder meets ASTM B-32 standard. Kit contains: 1/4 lb., .117" gauge silver lead free solder, 1.7 Oz. H-20-5 water soluble flux, an applicator brush and a sand cloth.