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Black aluminium seat-post adapter sleeve, 27.2 mm inner to 30.4 mm outer, 60 mm long

Unique-Bargains

Unique-Bargains Seat Post Adapter 27.2-30.4mm 60mm Black

SKU CH-VRWT-R2XRX

Aluminium alloy sleeve adapts a 27.2 mm seat post to a 30.4 mm frame tube, 60 mm long, black finish

  • TypeSaddles, Seats & Seat Posts
  • Converts 27.2mm seatposts to fit 30.4mm frames
  • 60mm aluminium sleeve installs tool-free in seconds
  • Anti-slip alloy surface holds post securely without cutting
  • Corrosion-resistant black finish suits mountain and road bikes
  • Lightweight adapter adds no measurable bulk to the build

Seat-post adapter 27.2 to 30.4 mm

This aluminium-alloy sleeve converts a 27.2 mm seat post to fit a 30.4 mm frame seat tube. It suits mountain bikes, road bikes and other common bicycles where the post diameter is smaller than the frame opening. The 60 mm length provides adequate overlap for a secure clamp. Installation requires no tools, drilling or cutting and takes only seconds.

Sustained load behaviour

Under continuous riding forces the alloy body resists deformation and maintains a tight fit between post and frame. The anti-slip surface prevents the seat post from rotating or sinking during long climbs or rough terrain. No play develops over time because the sleeve does not rely on compression inserts that can fatigue.

Thermals noise and power

As a passive mechanical component the adapter generates no heat, produces no noise and draws no power. The black anodised finish resists corrosion in wet conditions without adding measurable weight. Riders who need a larger diameter increase or a different clamp standard will need a separate solution.

Highlights

  • Converts 27.2mm seatposts to fit 30.4mm frames
  • 60mm aluminium sleeve installs tool-free in seconds
  • Anti-slip alloy surface holds post securely without cutting
  • Corrosion-resistant black finish suits mountain and road bikes
  • Lightweight adapter adds no measurable bulk to the build

Specifications

BrandUnique Bargains
TypeSaddles, Seats & Seat Posts

Questions about this item

Does the aluminium-alloy sleeve generate any noise or heat during long rides?

The aluminium-alloy sleeve is a passive mechanical part with no moving components, so it produces no noise and no measurable heat during extended use.

What must already be on the bike for this 27.2 mm to 30.4 mm adapter to work?

The bicycle needs a seat tube with a 30.4 mm inner diameter to accept the adapter's outer diameter and a seat post measuring 27.2 mm to fit the adapter's inner diameter.

Will this 60 mm long black adapter work with an older steel seat post and carbon frame?

The adapter fits any 27.2 mm post into any 30.4 mm tube regardless of frame or post material, provided both diameters match the 27.2 mm inner and 30.4 mm outer dimensions.

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