I use a 15watt for alot of things, controllers , leds small 30awg wire, chips, heavier wire i use a 25 watt and for desoldering i use a 40watt soldering iron, and or desoldering iron which i think is around 40 or 50 watt, desoldering tools or desolder bulb. solder it depends on what i am soldering and flux once in a while depending on what it is I am soldering.