[Lifetime Warranty] 99944200903 Speed-Feed 450 Trimmer Head (2026 Upgraded) - Pack of 2

99944200903 Speed-Feed 450 Trimmer Head - Pack of 2

Key Features

• Quantity: 2 trimmer heads
• Type: Bump-feed, fast-reloading head
• Diameter: 4.5 inches
• Line Capacity: Holds up to 20 ft of 0.095-inch trimmer line
• Arbor Size: 10mm x 1.25mm Left-Hand Thread (LH)

Replaces / Cross-Reference Part Numbers

• Echo: 99944200903, X047000940
• Shindaiwa: 28820-08000, 78890-21001

Compatibility & Fitment

• Designed for Echo and Shindaiwa straight shaft trimmers.
• Fits Echo models including: SRM-225, SRM-266, SRM-266S, SRM-266T, and SRM-266U.
• Verify your equipment requires a 10mm x 1.25mm LH arbor before purchasing.

When to Replace

• Housing is cracked, broken, or exhibits excessive wear.
• Bump knob is worn through, preventing line feed.
• Line consistently fails to advance or jams inside the head.
• Head causes excessive vibration or wobbles during operation.

Installation Tips

• Turn off the engine and disconnect the spark plug for safety.
• Lock the trimmer's gearbox to prevent rotation while removing the old head.
• Clean any debris from the arbor threads before installation.
• Thread the new head on counter-clockwise until firmly seated.