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 0.6mm / .02" diameter in standard 60/40 formulation. This is not lead-free solder, so not for lead-free/RoHS shops. However, for kit builders its 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 any SMT/fine-pitch work as it allows you to deposit small amounts of solder.This is "60/40" leaded solder with 40% Pb (Lead), 59.5% Sn (Tin) and trace Ag (Silver) %0.015, Cu (Copper) %0.04. Sometimes this is referred to as [59.5/0.015/0.04]