4AN Male to 1/8" NPT – 90-Degree. A gauge head adapter to connect your gauges with Earl's lines and fittings.
Earl's 968604ERL Gauge Head Adapter
Auto Meter 0 to 50 psi Digital Tire Pressure Gauge Head w Memory Pro-Comp
Earls 581404ERL Earls AN Port Plug - Hex Head
10 to 160 psi Large Bore Dual Head Chuck Service Pencil Tire Pressure Gauge
P20 HUD OBD2 Head Up Display GPS OBD Gauge Digital Speedometer Projector RPM