Without further delay let's begin exploring the Polymer Lithium Battery Spot Welding Pen for 709A/709AD Spot Welding Machine, also known as the HB-71B Spot Welding Pen.
This user-friendly welding pen with a U-shaped interface and one-piece design is designed to solve the difficulty of earthing during welding.

When put to the test this spot welding pen proved to be an excellent addition to any welding machine. With a solder pin spacing of 0.3cm and a maximum welding pulse current of 500A, it provides the necessary power and precision for efficient welding. The cable length of 630mm x2 and cable cross-section of 18mm⊃2; ensure a reliable connection and durability. The Ф 1.5mm x 7mm solder pin size is perfect for welding small parts, and the one-piece design makes it easy to handle with one hand.

In other words the HB-71B Spot Welding Pen is an excellent addition to any spot welding machine. However, it's worth noting that the copper cable is not fully insulated, which could be a potential safety hazard during use.

To put it simply if you're in the market for a reliable and user-friendly spot welding pen for your 709A/709AD Spot Welding Machine, this product should definitely be on your list. Despite its minor flaw, the HB-71B Spot Welding Pen provides excellent power and precision for efficient welding.