KUNGJUER 3-Piece Thread File Set — Metric & SAE Thread Chasers, Heat‑Treated Carbon Steel with Black Oxide Finish

KUNGJUER 3Pcs Thread File Set is a compact, professional-grade kit that restores damaged external threads in both metric and SAE sizes quickly and accurately.

When threads on bolts, studs, screws or pipes are worn or marred, replacing the entire fastener or component isn’t always necessary. This three-piece thread chaser set covers a wide range of metric and SAE sizes so you can re-cut and clean external threads on-site, saving time and money. Built from heat-treated carbon steel with a black oxide finish and supplied with removable handles and protective end caps, the kit is designed for repeatable precision, corrosion resistance, and safer handling in workshops and field environments.

Which thread sizes are included and will they fit my fasteners?

The set includes one metric chaser and two SAE chasers (UNF and UNC patterns) to cover common thread pitches. The metric file lists sizes from 0.75mm up to 3.00mm, while the SAE UNF and UNC files cover a broad range of fine and coarse American sizes. Check your fastener’s pitch or compare against included markings to select the matched tooth pattern for accurate restoration.

• Metric file: 0.75mm, 1.00mm, 1.25mm, 1.50mm, 1.75mm, 2.00mm, 2.50mm, 3.00mm
• SAE UNF file: sizes 9, 10, 12, 16, 20, 27, 28, 32
• SAE UNC file: sizes 11, 12, 13, 14, 16, 18, 20, 24
• Marked grooves let you match file rows to your fastener pitch quickly

How durable and precise is this thread repair tool?

Each file is forged from carbon steel, heat-treated for hardness and stability, and finished with a black oxide coating that helps resist rust and reduces glare while working. The hardened teeth are cut to maintain profile accuracy through repeated use, so you get consistent restoration without rounding or undersizing threads. For best results, use light, controlled passes and keep the chaser aligned with the original thread angle.

• Heat-treated carbon steel for long wear resistance
• Black oxide finish for corrosion resistance and reduced reflection
• Precision-cut teeth maintain thread form through multiple repairs
• Recommended: align carefully and use steady, light strokes

What accessories and safety features come with the set?

The kit includes a removable, ergonomic handle that improves leverage and reduces hand fatigue during repetitive work. Protective end caps are supplied to cover sharp file ends when stored or transported, and the compact size makes the set easy to carry in a toolbox or field bag. These conveniences help prevent accidental injury and protect the file teeth when not in use.

• Removable handle for improved grip and torque control
• Protective end caps to shield teeth and hands
• Compact footprint fits standard toolboxes and work belts
• Simple storage reduces wear during transport

Will this work for professional and DIY repair needs?

The KUNGJUER chaser file set is intended for both hobbyists and professionals who need to restore external threads without replacing parts. It’s suitable for automotive chassis work, engine maintenance, piping, machinery upkeep, and general workshop repairs. While not a substitute for re-cutting internal threads or complete fastener replacement in critical aerospace or medical contexts, it excels at routine maintenance and on-the-spot fixes.

• Useful for mechanics, fabricators, plumbers and maintenance techs
• Ideal for on-site repairs where quick thread restoration saves time
• Not intended for precision rethreading of critical aerospace/medical parts
• Pairs well with simple thread gauges to confirm pitch before use

Who is this for: The KUNGJUER 3Pcs Thread File Set is made for professionals and DIYers who frequently encounter damaged external threads and need a compact, durable kit to restore fasteners quickly. If you maintain vehicles, industrial equipment, piping systems, or electrical enclosures and want a reliable, portable solution for thread clean-up, this set covers common metric and SAE sizes and is ready for workshop or field use.