What it does: Insulation-piercing wire terminals that make electrical contact with insulated wires without cutting or stripping the insulation. Use by twisting the bottom and moving the black spring terminal to penetrate the insulation of 14 AWG to 22 AWG wires (0.03 to 0.18 inch diameter). Key benefits: Non-destructive testing: Provides reliable electrical contact while preserving wire insulation and reducing the risk of wire damage. Fast and convenient: Installs quickly by twisting the base and engaging the black spring terminal—no stripping, soldering, or wire separation required. Accurate measurements: Designed for stable contact to support voltage measurement and diagnostic work. Compatibility and sizes: Works with 14 AWG to 22 AWG wire sizes (0.03–0.18 in / ~0.8–4.6 mm diameter). Two standards available: 2 mm and 4 mm, to match common test lead or connector setups. Performance and use: Maintains contact on insulated conductors for diagnostic and repair tasks. Spring terminal design holds the probe in place for repeatable readings. Practical applications (real scenarios): 1. Automotive diagnostics: Measure voltage on vehicle wiring harnesses or sensor leads without cutting or re-terminating wires during troubleshooting. 2. Appliance and electronics repair: Quickly test power and signal lines inside devices where stripping individual wires is impractical. 3. Equipment maintenance: Take on-site voltage checks on control panels and bundled harnesses while keeping wiring intact. Why choose these terminals: Preserve wiring integrity during testing. Simplify and speed up diagnostic work. Available in two size standards (2 mm / 4 mm) and compatible with a broad range of common wire gauges (14–22 AWG, 0.03–0.18 in).