4mm Bore 604ZZ Bearing Roller Wheels

1) Rubber-Coated Compact Idler Wheel — 4×14×4 mm

A space-saving idler wheel designed for tight assemblies. The 14 mm OD and 4 mm width make it easy to fit into small frames, while the rubber surface helps damp vibration and reduce running noise.

• Bearing: 604ZZ (shielded)
• Size: 4 mm ID × 14 mm OD × 4 mm W
• Surface: black rubber-coated
• Typical uses: model mechanisms, small conveyors, hobby robotics, compact sliding/guide setups where quiet operation is preferred

2) Rubber-Coated Bearing Roller — 4×15×4 mm

This variant adds a touch more diameter for improved contact and slightly better load spread, while keeping the same slim profile. It's a practical choice when you want the feel of rubber traction without increasing overall width.

• Bearing: 604ZZ (shielded)
• Size: 4 mm ID × 15 mm OD × 4 mm W
• Surface: black rubber-coated
• Typical uses: printer carriage guides, drawer/rail assists, light automation rigs, workshop jigs with frequent back-and-forth motion

3) POM-Coated Guide Pulley — 4×16×6 mm

A low-friction guide pulley with a POM (acetal) outer wheel for smooth rolling and good dimensional stability. The larger diameter and increased thickness support steadier tracking in guided motion paths.

• Bearing: 604ZZ (shielded)
• Size: 4 mm ID × 16 mm OD × 6 mm W
• Surface: white POM-coated
• Typical uses: 3D-printer motion guides, curtain/track systems, fixtures exposed to light moisture where corrosion-resistant materials are valued

4) Nylon Bearing Disc — 4×15×6 mm

A balanced, medium-profile wheel intended for stable guiding and consistent rotation. The nylon outer wheel provides a controlled, quiet roll and is well-suited to general mechanical guidance and light support roles.

• Bearing: 604ZZ (shielded)
• Size: 4 mm ID × 15 mm OD × 6 mm W
• Surface: white/translucent nylon-coated
• Typical uses: furniture upgrades, small support rollers, fitness equipment guiding/stabilizing points, prototyping and test rigs

5) Plastic-Coated Wheel Bearing — 4×18×8 mm

Designed for applications that benefit from a wider rolling surface and added stability. With an 18 mm OD and 8 mm width, this model is often chosen where the wheel also needs to absorb small impacts or reduce slip.

• Bearing: 604ZZ (shielded)
• Size: 4 mm ID × 18 mm OD × 8 mm W
• Surface: durable white plastic-coated
• Typical uses: compact conveyor sections, light-duty door/guide mechanisms, shop carts and fixtures, assemblies needing steadier rolling contact

6) Wide Heavy-Duty Coated Roller — 4×17×11 mm

A thick, supportive wheel designed for higher stability and better side-to-side control in dusty or impact-prone environments. The 11 mm width makes it a good pick when you want a "more planted" roller feel without increasing bore size.

• Bearing: 604ZZ (shielded)
• Size: 4 mm ID × 17 mm OD × 11 mm W
• Surface: resilient white coating
• Typical uses: industrial shelving guides, rugged fixtures, under-structure guiding points, equipment exposed to debris/light shock where smooth but controlled rotation is needed

Quick Selection Tip (Practical)

• Choose 4 mm width models when clearance is tight and load is light.
• Step up to 6–11 mm width when you need better stability, smoother tracking, or longer service life in frequent-duty motion.