Weller Modular Heater for Thread-on Tip, 45 Watt, 900AF Product Details Catalog No. 4037S UPC Code 037103032010 Fits Tool(s) 7400/7500/7760/7770 Description Heating Element Packaging Industrial Box/Carton Tech. Spec. Solder_Safety_Warnings.pdf Low Res. Image 537S_100.jpg High Res. Image 537S_300.jpg Stock Item Normal Stock Item Package Details (Dimensions) Product Features: Used with standard series modular irons SL325, SL335, SL345 and SL500