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Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers
Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers
Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers
Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers
Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers
Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers

Mitsuboshi Super KB Standard V-Belt 0.5 in. W X 39 in. L For Riding Mowers

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Support American manufacturers + independent hardware retailers in one purchase.

Mitsuboshi Super KB Standard V-Belt is a precise, durable replacement belt engineered for riding mowers. Sized at 0.5 in width and 39 in length, this belt follows the 4LK profile t…

Mitsuboshi MPN 4LK390A
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Typical store price: low $15.99, average $18.99
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About Product Overview

Mitsuboshi Super KB Standard V-Belt is a precise, durable replacement belt engineered for riding mowers. Sized at 0.5 in width and 39 in length, this belt follows the 4LK profile to deliver dependable power transfer across your mower’s drive system. Encased in a protective sleeve, it arrives ready to install as a standard-length solution within the Super KB family.

  • Belt type: V-Belt
  • Series: Mitsuboshi Super KB
  • Profile: 4LK
  • Width: 0.5 in
  • Length: 39 in
  • Color: Beige
  • Packaging: Sleeve
  • Style: Standard
  • Used with: Riding mowers

Why choose this belt for your riding mower? The 4LK profile is specifically designed to align with standard drive pulleys found on many riding mowers, ensuring consistent tension and smooth power transfer. The Mitsuboshi build emphasizes reliable performance under routine mowing conditions, helping to minimize slipping and uneven blade engagement that can occur with worn or ill-fitting belts.

Ideal use cases include replacing a worn or stretched belt on a riding mower with a commonly specified 39-inch length and 0.5-inch width, ensuring you maintain optimal drive efficiency and mower response. This belt is well-suited for a variety of mower brands that use the 4LK standard and a 0.5" width, providing a straightforward, OEM-compatible replacement option.

Practical tips for installation and care: verify the belt length and profile match your mower’s OEM specifications before replacing, route the belt according to your mower’s belt diagram to avoid misrouting, and apply proper belt tension per your manual after installation. Regularly inspect for signs of wear—cracks, glazing, or fraying—and replace promptly to maintain consistent performance and prevent unexpected downtime.

For a dependable, maintenance-friendly drive belt that aligns with riding mower needs, the Mitsuboshi Super KB Standard V-Belt (0.5 in W x 39 in L, 4LK) offers a precise, durable solution built to keep your mower moving efficiently from season to season.

The Details Specifications

Brand Mitsuboshi
SKU 21435
UPC 034494543903
Unit 0
Case Pack Quantity 1 per case
Retail Unit Quantity 1
Unit of Measure 0 0
Dimensions (L × W × H) 18 × 3 × 1
Weight 0 lbs
Cubic Feet 0.02626 ft³
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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