Armsol 50w Nickel Plated Spade 7mm Soldering Gun Bit. The Soldering bit is a High-Quality Soldering Iron Tip. This is a Nickel Plated 3mm 50 Watt Bevel tip; it can be used with Armsol 50 W soldering iron. Upgrade your soldering gun with a new tip, you’ll get better & faster solder joints and the whole process will be much more enjoyable. This tip fits all analog and digital irons, and they’re fast to swap, takes only 30 seconds to change out. All the tips are good for either lead or lead-free (simply set the iron to the temperature required for the solder you are using).