Design and Compatibility The FJ5986-1212S is a straight splicer engineered for R134a systems, featuring -12 hose barb connections on both ends and an integrated low-side service port (13 mm). Based on the Aeroquip E‑Z Clip System configuration commonly referenced by Weatherhead/Danfoss, it enables field‑attachable connections without specialized crimp equipment. The carbon steel body is sized for #12 barrier hose with a 0.75 in hose-end bore, measures 5.6 in overall length, and weighs 0.28 lb—providing a durable, compact solution for repair splices and line modifications in automotive and industrial A/C applications.

Service Access and Field Performance The built‑in low-side port streamlines charging, evacuation, and pressure diagnostics without adding tees or extra joints, helping maintain system integrity. The -12 barb geometry supports secure, leak‑resistant engagement with the E‑Z Clip system, making it well suited for heavy‑duty trucks, buses, and off‑highway HVAC where uptime and serviceability matter. Its compact form factor aids routing through tight compartments, while the robust steel construction stands up to demanding A/C environments. Cross‑references include Eaton/Weatherhead FJ59861212S and other industry numbers, allowing this splicer to integrate seamlessly as a splice or repair component within existing R134a hose assemblies.