SRA Low Temperature Lead Free Solder Paste T3 - 15 Grams (SSLTNC-15G) [Misc.] This is a low temp solder paste with a no clean flux Melting Point 137C 278F (Eutectic) 87% Metal Particle Size 25-45 Microns Protect Sensitive Parts with this low melting Lead Free Solder Sn42/Bi57/Ag1 This alloy is better than Sn42/Bi58 because it contains Ag which makes it stronger and less brittle