Weld On Stainless Steel O2 Bung

The ISR Performance Weld-On O2 Bung is a stainless steel weld-in fitting threaded for 18mm x 1.5 sensors. The universal solution when you need to add an O2 sensor port: wideband installs, custom downpipes, or supplementing an exhaust that didn't come with a downstream bung from the factory.

What It Does

O2 bungs are the threaded fittings welded into exhaust piping that hold O2 sensors. The 18mm x 1.5 thread pitch covers most narrowband and wideband O2 sensors on the market (Bosch LSU 4.9, AEM, Innovate, NGK, and so on). Stainless steel construction holds up to the heat cycling and chemical exposure that would corrode mild steel bungs over time.

Fitment

Universal. Welds into any exhaust piping. Fits sensors with 18mm x 1.5 thread pitch. the standard for most aftermarket wideband and OEM-replacement narrowband sensors. Verify your specific sensor's thread spec before ordering. Common applications: custom downpipe builds, adding wideband bungs ahead of the cat, retrofitting a missing O2 location on an aftermarket exhaust (relevant for our IS-CSEXH-NC NC Miata exhaust, which doesn't ship with a bung).

Product Details

Brand: ISR Performance

Part Number: IS-O2B

Type: Weld-on O2 sensor bung

Material: Stainless steel

Thread Pitch: 18mm x 1.5

Application: Custom downpipes, wideband install, missing O2 location retrofits

Installation: Weld-in (TIG or MIG welding required)

Sold: Individually

Legality: Off-road and competition use only