Replacement Double Flat 2.4mm Tip for the WLBU75 Weller Cordless Butane Soldering Iron. The Double Flat is easy to replace without a tool and is perfect for your electronic soldering tasks. Solder on-the-go with Weller's Soldering Iron & Heat Tool. 25W-75W butane provides continuous no-stop soldering. With quick and easy butane refills, wide range of tips, auto shut off, and the ability to convert for hot air/torch applications, it's perfect for your soldering tasks.