.product-info-tutorial{margin-bottom:20px;}.product-tutorial-img-container{width:20%;}.product-tutorial-img-container img{margin:0;} High quality rosin core welding wire. Easy to solder, smooth flow, fasts soldering speed, and strong soldering point. Great soldering ability, especially suitable for circuit board, DIY, home improvement, cable/TV/radio/stereo/toys and other electronic devices maintenance. If you want to make a kit you'll need some solder. This 0.1 lb (about 50 grams) spool is a good amount, not too much (like 1 lb spools) and not too little (like those little 'pocket clip' vials).This spool of solder contains approximately 0.8mm / .02" diameter in with lead-tin formulation. This is not lead-free solder, so not for lead-free/RoHS shops. However, for kit builders, it's a joy to use, much easier than lead-free, and great for beginners. For flux, it contains a 'no clean' rosin core. This diameter solder is best for through-hole soldering as its a bit thicker than 0.5mm or 0.3mm, but it could be used for SMT/fine-pitch work as well, if you're in a pinch.This is "60/40" leaded solder with 37% Pb (Lead), 63% Sn (Tin) and trace Ag (Silver), Cu (Copper). Even though this is not truly 60/40, it is close enough for us to consider it a replacement.