GDK1939M Gauging Drill Kit (#19–39, Metal Box) Gas Orifice Drill Bits

Special Order Item 7 to 10 Day lead time

The GDK1939M Gauging Drill Kit (#19–39, Metal Box) is the technician‑grade orifice‑sizing kit used for natural‑gas and LP burner tuning. Manufactured by Anderson & Forrester, this set includes drill sizes #19 through #39, covering the most common orifice ranges used in furnaces, water heaters, RV heaters, and mobile‑home heating equipment.

The metal storage box provides superior durability compared to the standard plastic case, making it ideal for service trucks, field kits, and high‑use technicians who need long‑term protection for precision bits.

Included Sizes (#19–39)

• 21 precision‑ground orifice drills

• Accurate sizing for NG/LP combustion

• Heavy‑duty metal case (GDK1939M variant)

• Same drill set as GDK1939 — upgraded enclosure

Typical Applications

• Burner orifice sizing

• BTU output tuning

• Combustion calibration

• Mobile‑home furnace service

• RV furnace orifice adjustments

• Water heater orifice checks

Cross‑Reference Part Numbers

Grounded from shopping results:

• GDK1939