SAVE
$6.28
Representative image of an RCScrewZ metal-shielded bearing kit for Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028); exact bearing sizes and quantities vary by RC model.
Upgrade Your RC Car with Metal Shielded Bearings for Losi Lasernut 2.2 LOS03028 | los120b - High Performance Upgrade | Durable & Reliable - by J-M SUPPLIES
Infographic: 'Choose Wisely for Your Need for Speed' – Highlights Metal Shielded Bearings as the top choice for unbeatable on-road RC car performance -
Infographic: 'Choose Wisely for Off-Road Adventuring' – Recommends Rubber Sealed Bearings for maximum protection and enhanced off-road performance in RC vehicles -
Infographic: 'Choose Wisely for Your Need for Speed' – Highlights Metal Shielded Bearings as the top choice for unbeatable on-road RC car performance - LOS120b
Infographic: 'Choose Wisely for Off-Road Adventuring' – Recommends Rubber Sealed Bearings for maximum protection and enhanced off-road performance in RC vehicles - LOS120b
Infographic: 'What Matters Most to You? Performance on the Streets or Durability in the Dirt?' – Guides on selecting bearings to match your RC lifestyle, highlighting the importance of choosing based on whether your focus is speed on paved roads or resilience in off-road conditions - LOS120b
Infographic: 'Need Bearings? How to Check Your RC's Bearings for Replacement' – Instructions to remove, clean, and inspect bearings for gritty texture or improper movement, indicating the need for replacement - LOS120b
Step-by-Step Guide: Checking RC Bearings. 2. Assess if bearings feel gritty or aren't spinning freely. 3. Non-free spinning bearings impair RC performance. 4. Bearings not spinning freely may need replacement - LOS120b
RCScrewZ and J-M SUPPLIES offer high-quality RC bearing kits, available as metal shielded or rubber sealed options, suitable for diverse RC needs - LOS120b
Elevate Your RC Adventure! Image introducing Stainless Screw Kits as the Ultimate Upgrade. Offers enhanced durability, superior corrosion resistance, and a sleek look, making them a top choice for complementing high-quality bearing selections. Trusted by RC enthusiasts worldwide - LOS120b
Infographic on RCScrewZ Bearing Kits: Highlights features of both metal and rubber shielded bearing kits, detailing high-quality components suitable for various RC models. Covers standard, flanged, one-way, and thrust bearings included in kits, with extra spares. Explains the shielding and performance benefits of each type, tailored for specific RC model needs - LOS120b
Infographic reminder: Refer to the item description for more detailed information about the product - LOS120b
Infographic reminder: Refer to the item description for more detailed information about the product - LOS120b
Notice: Check the product description for detailed information on the specific bearing sizes included in this bearing kit - LOS120b

Why Choose This Kit

Key features and intended use for this kit.

Shield type

Metal-Shielded (On-Road)

Performance focus

Low-drag, not sealed

Best suited for

Cleaner on-road / prepared surfaces

Metal-Shielded Bearings

RCScrewZ Metal Shielded Bearing Kit los120b for Losi Lasernut U4 2.2 RTR Brushless 1/10 Electric 4WD Rock Racer Desert Buggy (LOS03028) | SET

RCScrewZSKU: los120b

Model-specific metal-shielded bearings for smooth, low-drag operation on cleaner on-road or prepared surfaces.

Fits: Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028)
OEM / model: LOS03028

US
Regular price
$53.67
Sale price
$53.67
Regular price
$59.95

In stock

View Cart

Confirm this kit fits your RCMatch the RC model and OEM/model number shown above to your vehicle.

Exact model check

Confirm This Fits Your RC

Match the RC model and OEM/model number below before ordering.

RC model
Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028)
OEM / model number
LOS03028
Kit type
Metal-Shielded Bearing Kit — Low-Drag for Cleaner Running
Scale
1:10
Power
Electric
View all verified kits for this model →
More compatibility details
RC brand
Losi
Vehicle class
Land
Kit SKU
los120b
Model series
Lasernut, Lasernut U4, Tenacity, U4 Rock Racer
Product information

Everything You Need Before Ordering

Review what is included, installation notes, shipping details, and complete kit information.

Kit Contents & Installation

What’s Included Model-specific bearing kit; review the listed sizes and quantities.
  • Bearing sizes listed below for this model-specific kit
  • Quantities and any spare bearings are included only when specifically confirmed in the product details.
  • Review the product-specific bearing sizes and styles below or in the full description.

Included bearing sizes for this kit:

  • 5x8x2.5mm bearings
  • 5x11x4mm bearings
  • 6x12x4mm bearings
  • 10x15x4mm bearings
  • 12x18x4mm bearings
Installation & Model NotesImportant instructions and model-specific guidance.

Seat bearings fully and squarely. Do not force them into the housing or overtighten the hardware that retains them.

Keep metal-shielded bearings clean and dry.

After cleaning and drying, apply a small amount of light bearing oil.

Details & Support

Kit Details Lower-drag metal shields for clean, dry running conditions.
Shield Type
Metal-Shielded Bearings
Performance Priority
Lower drag
Protection
Not sealed; best kept clean and dry
Best For
Cleaner on-road or prepared surfaces when lower drag is the priority
Not Ideal For
Dust, dirt, sand, mud, water, or frequent wet-condition use
Prefer Rubber-Sealed?
Choose Rubber-Sealed bearings when protection against dirt, dust, and debris matters more than the lowest possible drag.
Shipping & Returns Handling time, current delivery estimate, and return policy.
Free shipping on all U.S. orders (USPS Priority Mail).
Ships within 1–2 business days (Mon–Fri); some Saturday shipments by 12:00 PM ET.
Most orders ship from Canton, MI 48187. APO/FPO/DPO & PO Boxes welcome.
Priority Mail typically delivers in 2–3 business days (estimates; not guaranteed).
Easy 30-day returns with prepaid USPS label; refunds issued within 3 business days after the return is received.

Over 99% positive over ~14,000 orders on eBay (last 12 months) — as of October 2025. View on eBay

Full Product Description Read the complete product specifications and details.

Exact RC Model Fitment

Confirm the exact RC model and RC vehicle OEM/model number below before ordering.

Compatible RC Model
Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028)
Compatible RC Brand
Losi
RC Vehicle OEM / Model Number(s)
LOS03028
RCScrewZ Kit Part Number
los120b

Vehicle Compatibility Details

Review these vehicle details to help confirm compatibility with your RC model.

RC Vehicle OEM / Model Number(s)
LOS03028
RC Chassis Compatibility
Losi Lasernut U4 Tenacity 4WD Rock Racer
Compatible Vehicle Type
1/10 Electric 4WD Rock Racer Desert Buggy
Terrain Compatibility
Compatible Scale
1:10
Compatible Fuel Type
Electric

What Is Included

Included bearing sizes for this Metal-Shielded Bearing Kit:

  • 5x8x2.5mm bearings
  • 5x11x4mm bearings
  • 6x12x4mm bearings
  • 10x15x4mm bearings
  • 12x18x4mm bearings

What Is Not Included

Only the bearings identified in the included-bearing-size list are part of this kit. 

The RC vehicle and separately sold parts are not included unless specifically listed.

Installation & Model Notes

Metal Shielded Bearing Kit Compatibility:

Quick Fit Summary:

  • Compatible Brand: Losi

  • Fit: Model-specific fitment for Losi Lasernut U4 2.2 RTR Brushless

  • Compatible RC Model/OEM Numbers: LOS03028

  • Scale: 1/10

  • Power Source / Fuel Type: Electric

  • Battery / Cell Count: 4S

  • Drive Type: 4WD

  • Vehicle Type: Rock Racer / Desert Buggy

  • Chassis: Losi Lasernut U4 Tenacity 4WD Rock Racer

  • Era: Next Gen Era (2020–Present)

  • OEM / Models: LOS03028

  • RC Model Terrain: Off-Road: Rock, Desert, Dirt & Gravel

This Kit Details:

  • SKU: los120b

  • MPN: los120b

  • Kit Type: Metal Shielded Bearing Kit

  • Bearing Type: Metal-Shielded (On-Road / Low-Drag)

  • Sealed Bearings: No

  • Water/Dust Protection: Low-drag, not sealed

  • Product Material: Carbon Chrome Steel Bearings

  • Product Color: Silver

Bearing Size Details:

  • 5x8x2.5mm bearings
  • 5x11x4mm bearings
  • 6x12x4mm bearings
  • 10x15x4mm bearings
  • 12x18x4mm bearings

OEM / Model Code / Alias Coverage:

  • Verified OEM / model codes: LOS03028

  • Series / search aliases: Lasernut, Lasernut U4, Tenacity, U4 Rock Racer

Model Family Coverage:

Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028)

Product Benefits:

Metal shielded bearings are best for clean, dry, low-debris running, bench rebuilds, display builds, and racers who prefer reduced friction and a lower-drag drivetrain feel.

Fitment Note:

Confirm your RC model and OEM number before ordering. This kit is matched to Losi Lasernut U4 2.2 RTR Brushless and the listed OEM/model codes.

Search-Friendly Notes:

Compatible Losi and TLR parts support for Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028); useful for RC screw kit, RC bearing kit, rebuild, upgrade, race prep, and maintenance searches.

Metal-Shielded Bearing Kit Details

Review the bearing-kit details below before ordering.

RCScrewZ Kit Part Number
los120b
Product Brand
RCScrewZ
Shielding Type
Metal-Shielded (On-Road)
Sealed Bearing Status
No
Bearing Material
Carbon Chrome Bearings
Approximate Piece Count
Color
Silver

Before Ordering

  • Confirm your exact RC model, RC brand, and OEM/model number whenever possible.
  • Review the included-bearing-size list before purchase.
  • Read the installation and model notes before disassembly or installation.

Vehicle versions, chassis revisions, and model-year configurations can differ. 

Confirm fitment before purchase when your RC vehicle differs from the details shown above.

Share This Kit

Know another RC owner who could use this kit? Send them this exact product page.

More ways to share:

Customer Reviews

Same-model kit options

More Verified Kits for This RC Model

These kits are verified for the same exact RC model and OEM/model number.

Stainless Screw Kit

For Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028) OEM/model: LOS03028
Current price: $38.94 Compare-at price: $43.95 Save $5.01 In stock View Stainless Screw Kit

Rubber-Sealed Bearing Kit

For Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028) OEM/model: LOS03028
Current price: $53.67 Compare-at price: $59.95 Save $6.28 In stock View Rubber-Sealed Kit
Next step

Continue Shopping by RC Model

Shop More Parts for This RC Model View all verified kits for this exact model Find Parts for a Different RC Model Search by brand and model in the Compatibility Hub
Fits: Losi Lasernut U4 2.2 1/10 Electric 4WD Rock Racer (LOS03028)
$53.67