8Pair/16Pcs M18 x 1.5 Exhaust Lambda Boss Nut Weld on in 304 Stainless O2 Oxygen Sensor Bung. -O2 Oxygen Sensor Bung+Plug Kit. 8x Oxygen Sensor Nut Bung Stepped. -Easy to weld on. -Designed to adding a O2 sensor in any place you need.
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