Large 1lb rolls lead based solder in three diameters for most any soldering job. Necessary in combination with ruby fluid flux (above). Can also be used for plumbing and other soldering jobs.Note; Soldering Nichrome wire usually requires the use of silver base solder. However, if you liberally moisten the wire and substrate with Ruby Fluid and solder while wet, it works fine. Ruby Fluid promotes the flow and bonding of the solder melt.