For instructions on using these tools to solder surface mount components down to .5mm pitch, see our surface mount soldering guides. The loupe is primarily used to check for sufficient solder and bridges on smaller pitches. The larger end can actually be held hands-free in your eye socket. The solder: Kester��� brand, 1oz, .02″ diameter, 63/37 (63% tin, 37% lead), #66 core (3.3% flux by weight), #285 RMA flux (RMA = Rosin Mildly Activated), flux is classified as ROL0 under IPC J-STD-004. What does all this mean? This solder will readily wick to metal surfaces, and it’s highly unlikely that cleaning is necessary. See the flux section of our soldering guide for more information about what all the parameters mean. solder data sheet Flux pen: Simply depress the tip to start flux flowing, then paint it on where needed. The main advantage of a flux pen over needle or brush applicators is that it’s easier to keep flux from spreading out to unneeded areas. The flux pen is also Kester��� brand, #186 rosin flux, RMA (mildly activated). Again, this is a very effective flux that in all likelihood does not require cleaning. Here’s the spec sheet. Note: flux is flammable and requires ground shipping through FedEx.