Female to Male Reducer Adapter; Female Size: -6AN; Male Size: -4AN 1998-pontiac-firebird-esi4271216 then this is it

then this is it

These silver powder coated springs fit perfectly with QA1's Pro Coil Shock Systems

This is essential for rear end centering after lowering the vehicle and for clearance when running larger tires

These direct bolt-on replacements will minimize wheel hop

Female to Male Reducer Adapter; Female Size: -6AN; Male Size: -4AN 1998-pontiac-firebird-esi4271216 then this is itVibrant Performance Female AN to Male AN Flare Reducer Adapters are lightweight and constructed from 6061 Aluminum Alloy. Our Female AN to Male AN Flare Reducer Adapters deliver quality, reliability, smooth flow, ease of assembly and the comfort of an anti leak seal and are designed to fit most popular oil pumps, fuel pumps, fuel filters and a wide range of other common components. All Vibrant Performance Adapter Fittings are available in anodized