Hi, I mostly solder my hobby electronics using SAC (Sn/Ag/Cu) 297 no-clean solder, but I have seen this Kester K100LD alloy as well. I read somewhere that is contains only Sn and Cu and I thought it to be better for safety purposes (why not reducing the metals to 2 instead of 3?). They have also the 296 no-clean version, which does not contain any halogens.