The Speedflow 819-05 -5AN 5/16" Tube Sleeve is designed for hardline AN plumbing where secure, leak-free connections are critical. Used with matching -5AN tube nuts, it supports proper sealing on flared tube ends in performance fuel, oil and hydraulic systems. Precision machined for reliability in street, track and motorsport fabrication. Features Suits -5AN fittings Designed for 5/16" OD hardline tube Precision machined for secure sealing Compatible with Speedflow -5AN tube nuts Suitable for fuel, oil and hydraulic systems Lightweight and corrosion-resistant construction Typical Applications Fuel hardline installations Oil system plumbing Hydraulic and clutch lines Custom hardline fabrication Street, track and race vehicle builds Fitment Notes Designed for use with 5/16" OD tube Must be paired with compatible -5AN tube nut Correct tube flaring required before assembly Not suitable for flexible hose applications