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Twenty small black rubber O-rings, 4mm inner diameter, half-millimetre cross-section

Unique-Bargains

Unique-Bargains NBR O-Ring 20pcs 4mm ID .5mm Width

SKU CH-ANDX-2NK6B

A 20-piece set of black NBR O-rings with a 4 mm inner diameter and 0.5 mm width for sealing oil and UV-resistant applications

  • 20 O-rings per pack keep spares on hand
  • NBR material resists oil and UV exposure
  • 4 mm inner diameter fits standard fittings
  • 5 mm cross-section provides reliable sealing
  • Black nitrile rubber withstands chemicals and abrasion

Essential Sealing Kit

This pack supplies twenty black nitrile butadiene rubber O-rings built for plumbing, machinery, hydraulic and pneumatic repairs. The NBR formulation delivers strong oil and UV resistance for reliable sealing in demanding environments.

Precise Dimensions Daily

Each ring features a 4mm inner diameter and a .5mm cross-section width, giving a thin profile that fits tight grooves. The super pliable construction and extra thick wall design handle high dynamic loads and resist abrasion during repeated assembly.

Upgrade From Basic Seals

The kit replaces standard rubber rings that degrade quickly when exposed to chemicals, oil or elevated temperatures. The jump is worth it when a repair demands higher chemical resistance and longer service life than ordinary elastomers provide.

How it compares

Measured against everything we stock in Caulking & Sealing Supplies, at today’s prices. Recalculated every night.

Price $3.99
Cheaper than about 95% of the 631 comparable items (median $16.99).

Specifications

Product
Brand nameUnique Bargains

Questions about this item

What inner diameter and cross-section do these NBR O-rings have?

Each ring has a 4 mm inner diameter and a 0.5 mm cross-section, giving a 0.16" ID and 0.02" width.

What groove dimensions will these 4 mm ID, 0.5 mm width rings fit?

They seat in a standard 4 mm ID groove with a 0.5 mm cross-section channel; the extra-thick wall tolerates slight groove wear.

How are these O-rings installed and what mistake should be avoided?

Lubricate lightly with compatible grease, stretch over the shaft into the groove, and avoid twisting the ring during seating.

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