Allinone design: builtin power supply and welding pen are integrated, eliminating the need for an external welding pen and simplifying setup for spot welding tasks. Portable and compact: lightweight, easy to carry, and suitable for both DIY enthusiasts and professionals. The builtin power supply enables convenient welding of nickel sheets in various locations. Easy charging: mini USB charging interface allows convenient charging from USB power banks, computers, or USB wall adapters. conductivity: the integrated soldering pen uses goldplated terminals for conductivity and low contact resistance, contributing to reliable welds. Performance and reliability: stable builtin power supply supports consistent spot welding of thin materials, helping achieve solid joints on nickel sheets. Compatibility and applications: designed for spot welding of nickel sheets in a range of DIY and professional projects, with a compact form factor that fits small workspaces. Use scenarios DIY battery pack construction: weld nickel strips to connect cells and form tab connections in compact electronics or energy storage projects. Electronics prototyping and repairs: spot weld thin nickel sheets or small metal components in hobbyist or professional electronics work. Onsite field work and prototyping: portable, selfcontained unit suitable for quick spot welds away from the main workshop.