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Flexfab KIT5003D heater hose repair kit hose and clamp kit

Flexfab 5515-138X12, 1.38" x 12 ft, 3-Ply Blue Silicone Coolant Hose, 35mm

by Flexfab
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$ 296.09
$ 296.09 - $ 296.09
$ 296.09
$ 236.89
$ 236.89 - $ 236.89
$ 236.89

A versatile heavy-duty coolant hose for diesel, automotive, marine, agricultural, and industrial cooling systems, the Flexfab 5515-138X12 is a 3-ply blue silicone hose built to resist hardening, cracking, cold leaks, and aging where ordinary rubber fails.

Why this Flexfab 3-ply coolant hose

  • 3-ply polyester reinforcement — 400 PSI actual burst, a wide margin over the ~133 PSI working pressure of most cooling systems.
  • −65°F to +350°F range — stays flexible in cold and handles under-hood heat without going brittle.
  • Meets SAE J20 R1 Class A & TMC RP303B Class I Grade II — documented spec-grade performance.
  • 1.38" (35mm) ID × 1.7" (43mm) OD — precise sizing for a clean clamp seal.
  • Resists oil splash, ozone, and direct sunlight — long service life in hostile engine environments.

Cut to a 12-foot stick, ready to install, and pairs with a Flexfab 2582-0020 clamp for a leak-free connection.

Backed by hpcouplers’ fast shipping and easy returns.

  • FlexFab Series: 5515
  • Part Number: 5515-138X12
  • Inside Diameter (ID): 1.38" (35mm)
  • Outside Diameter (OD): 1.7" (43mm)
  • Hose Length: 12 feet
  • Wall Thickness: .140" / .190"
  • Weight LB/FT: 0.44
  • Actual Burst Pressure - PSI: 400
  • SAE J20 R1 Class A - PSI: 250 PSI
  • TMC RP303B Class I Grade II - PSI: 125 PSI
  • Extreme temp range: -65F to +350F
  • Construction: Blue Silicone hose with 3-ply of Polyester reinforcement