{"product_id":"evil-energy-6an-male-to-3-8-5-16-hardline-compression-adapter-aluminum-body-brass-ferrule-37-flare","title":"EVIL ENERGY 6AN Male to 3\/8\" \u0026 5\/16\" Hardline Compression Adapter — Aluminium Body, Brass Ferrule, 37° Flare","description":"\u003cp\u003e\u003cstrong\u003eEVIL ENERGY's 6AN male to dual hardline compression adapter converts a 6AN 9\/16-18 UNF flare connection to both 3\/8\" and 5\/16\" stainless or aluminum hardline with a 37° sealed flare.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis compact adapter is built for mechanics, fabricators, and performance enthusiasts who need a reliable junction between standard AN plumbing and rigid hardline. Crafted from an aluminum alloy body and brass ferrule, the adapter provides a corrosion-resistant transition for fuel delivery, engine plumbing, and related systems. Its 37° flare sealing and precise 9\/16-18 UNF 6AN thread ensure a tight, repeatable connection when paired with compatible hardline materials.\u003c\/p\u003e\n\n\u003ch3\u003eHow does this adapter join AN fittings to rigid fuel or brake hardline?\u003c\/h3\u003e\n\u003cp\u003eThe adapter uses a traditional AN male flare on one end and a compression ferrule system for rigid hardline on the other. The 6AN male side threads into a 9\/16-18 UNF female AN port, creating a 37° metal-to-metal seal, while the ferrule compresses onto 3\/8\" or 5\/16\" hardline to create a leak-resistant mechanical hold.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e6AN male thread: 9\/16-18 UNF with 37° flare sealing\u003c\/li\u003e\n  \u003cli\u003eCompression end accepts 3\/8\" and 5\/16\" hardline\u003c\/li\u003e\n  \u003cli\u003eBrass ferrule compresses for a tight mechanical seal\u003c\/li\u003e\n  \u003cli\u003eWorks with stainless steel or aluminum rigid tubing only\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat materials and construction quality should I expect?\u003c\/h3\u003e\n\u003cp\u003eThe adapter body is machined from a durable aluminum alloy and fitted with a brass ferrule to resist corrosion while keeping weight low. These materials are common in automotive plumbing because they balance strength and resistance to fuels and oils without adding unnecessary mass.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eAluminum alloy body for strength and light weight\u003c\/li\u003e\n  \u003cli\u003eBrass ferrule for secure compression and corrosion resistance\u003c\/li\u003e\n  \u003cli\u003ePrecision threads (9\/16-18 UNF) for repeatable sealing\u003c\/li\u003e\n  \u003cli\u003e37° flare seating to match AN-standard ports\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhich systems and installations is this adapter suited for?\u003c\/h3\u003e\n\u003cp\u003eThis fitting is designed for non-flexible hardline runs in fuel delivery, return lines, vacuum or other engine bay plumbing where an AN connection must interface with rigid tubing. It’s commonly used in engine modifications, custom fuel systems, and retrofits where swapping between tube sizes is needed.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFuel delivery and return lines in performance engines\u003c\/li\u003e\n  \u003cli\u003eEngine bay and chassis hardline plumbing\u003c\/li\u003e\n  \u003cli\u003eCustom fabrication and retrofits requiring AN-to-tube transitions\u003c\/li\u003e\n  \u003cli\u003eNot intended for soft or rubber hose—use only suitable hardline\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eAny important installation notes or compatibility limits?\u003c\/h3\u003e\n\u003cp\u003eMeasure your tubing diameter and confirm material before installation because the compression ferrule is only compatible with stainless steel or aluminum hardline. Proper torque and thread sealing practice on the 6AN side are critical; avoid over-tightening the flare to prevent distortion of the sealing surface.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify 3\/8\" or 5\/16\" hardline diameter before purchase\u003c\/li\u003e\n  \u003cli\u003eUse only stainless steel or aluminum rigid tubing with ferrule\u003c\/li\u003e\n  \u003cli\u003eTighten AN threads to proper torque—do not overtighten\u003c\/li\u003e\n  \u003cli\u003eInspect ferrule seating and flare surface for damage before sealing\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: This EVIL ENERGY adapter is intended for professional mechanics, aftermarket tuners, and experienced DIY builders who need a compact, dependable solution to link AN plumbing with fixed-diameter hardline. If you work on fuel systems, engine plumbing, or custom fabrications and require a robust, lightweight transition piece, this adapter offers a precise, industry-standard connection—provided you are using compatible hardline materials and follow proper installation procedures.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Will this adapter fit soft rubber hose?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: No. It's designed for stainless steel or aluminum hardline only; use a hose-specific adapter for rubber lines.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: What thread size is the 6AN male?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: The 6AN male thread is 9\/16-18 UNF and seals on a 37° flare.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"EVIL ENERGY","offers":[{"title":"Default Title","offer_id":55165341663575,"sku":"B0FN3S9ZYJ","price":32.86,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/1524\/7191\/files\/evil-energy-6an-to-hardline-front-view.jpg?v=1790354899","url":"https:\/\/britishgarage.co.uk\/products\/evil-energy-6an-male-to-3-8-5-16-hardline-compression-adapter-aluminum-body-brass-ferrule-37-flare","provider":"British Garage","version":"1.0","type":"link"}