This capacitor is to use to suppress the voltage spikes if needed. You may need to use larger ones depending on your engine.
It is a stainless-steel curved notched M18X1.5 size bung and plug that you can use with wideband oxygen sensor when tune the engine.
APSX Wideband B2 faceplate kit to use for other PSI ranges
APSX Wideband D2 faceplate kit to use for other fuel types and lambda setting
APSX D1 Wiring Harness designed to use ONLY with APSX D1 AFR Controllers including D1-DIY board as supplement or D1 Wideband Controller as replacement.
APSX D2 Wiring Harness designed to use ONLY with APSX D2 AFR Controller Gauge.
APSX Wideband controllers and gauges use ONLY Bosch LSU4.2 (part# 17014).