EPCO has an expanded line of Zero-Leak Gold plugs that include a magnetic design that is ideal for applications like oil and transmission drain plugs. A magnet is mounted into these plugs to remove metal particles in fluid systems, which allows for cleaner, more efficient operation. Zero-Leak Gold magnetic plugs are available in all SAE and metric ISO sizes, and in both socket and hex head styles. And all provide zero-leak performance—guaranteed.

Two-Seal Design

Zero-Leak Gold plugs have two seals. The first seal is a metal-to-metal seal created by the engagement of a taper in the SAE J1926 or ISO 6149 port with a mating taper in the ZLG fitting design. This engagement is several thousands of an inch long for minimal gap and high unit loading. This engagement also causes the removal torque to be greater than the insertion torque, as documented in the Fluid Power Institute tests conducted at the Milwaukee School of Engineering. See the FPI Test Reports >
The second seal is an elastomeric O-ring seal located under the taper in the ZLG fitting, which acts as a backup seal should there be a failure with the primary seal. The Zero-Leak Gold O-ring cannot be extruded onto the spot face of the port, which prevents ZLG plug from “backing out” as SAE ORB Plugs counterparts are prone to do. The O-ring also cannot be forced into the interface of the threads of the plug or port where it could be nibbled or damaged.
zero-leak gold magnetic plug two seal diagram

ZLG Magnetic Drain Plug Advantages

Zero-Leak Gold magnetic plugs offer a number of advantages over SAE or ISO metric straight thread plugs.
  • Able to be resealed repeatedly without loss of effectiveness
  • Resealing will not damage plug or port threads
  • No chemical sealants required, eliminating risk of fluid contamination during removal and reinsertion
  • Guaranteed not to leak or back out, even in vibration, temperature change and pressure spike situations

ZLG Magnetic Plug Sizes

Magnetic Socket Head Plugs

Magnetic Hex Head Plugs

Custom ZLG Magnetic Plugs

Need a size or spec you don’t see here? Zero-Leak Gold magnetic plugs are available in custom configurations for unique applications.  Contact us for more info.

Magnetic Plug Applications

Zero-Leak Gold magnetic plugs are configured to replace the old style, O-ring only straight thread fill and standard magnetic drain plugs used in many transmissions and gear boxes today.

Access Ports


Agriculture Equipment

Automotive Equipment Rebuilders

Brake Systems

Construction Equipment

Diesel Engines

Fuel Dispensers

Gear boxes

Heavy duty truck transmissions

Marine Engines

Oil drain plugs

Off-Highway Equipment

Other OEM applications


Test Equipment

Transmission Drain/Fill Plugs