Indium-based solder melt at 275° F (150° lower than lead-tin solders, with a much higher wetting ability). Specific gravity is 8.6, while the bonding holding strength is 4,000lbs PSI. Will never tarnish; contains no silver or bismuth and will solder to platinum, golds, silver and numerous alloys. Solid-state components can be soldered without using a heat sink. Repairs to printed circuit boards are simple as the low melting point will not damage the board. use with any Flux, rosin, chloride or acid.