[Lifetime Warranty] 99944200903 Speed-Feed 450 Trimmer Head - Compatible with Echo SRM-266 SRM-266S SRM-266T SRM-266U SRM-280 SRM-280S SRM-280T - Replaces X047000940 - Pack of 2

99944200903 Speed-Feed 450 Trimmer Head for Echo String Trimmers - Pack of 2

Key Features

• Rapid Loading System:Designed to be reloaded in seconds without disassembling the head; simply align the arrows, feed the line through, and twist the bump knob.
• High-Capacity Spool:Accommodates up to 20 feet of .095" diameter line, reducing downtime during large residential or commercial clearing jobs.
• Smooth Bump Feed:Features a reliable internal spring mechanism that advances the cutting line consistently with a light tap on the ground.
• Universal Compatibility:Includes various arbor adapters to ensure a precise fit across a wide range of straight-shaft power heads.
• Durable Construction:Built with high-impact materials and a reinforced bottom cover to withstand contact with fences, rocks, and pavement.

Replaces / Cross-Reference Part Numbers

• 99944200903
• X047000940
• 99944200902
• 78890-21001
• Speed-Feed 450 Series

Compatibility & Fitment

• Echo SRM Series:SRM-266, SRM-266S, SRM-266T, SRM-266U.
• High-Power Models:SRM-280, SRM-280S, SRM-280T, SRM-280U.
• Additional Fitment:Compatible with many PAS (Pro Attachment Series) units and select models from Shindaiwa (e.g., T262, T282) using the included adapter hardware.
• Line Size:Best suited for .095" and .105" professional-grade trimmer lines.

When to Replace

• Worn Bottom Cover:The "bump" surface is ground down or has holes, preventing the internal spring from functioning correctly.
• Eyelet Damage:The metal eyelets where the line exits are grooved or missing, causing the line to snap prematurely.
• Stuck Loading Mechanism:The internal spool no longer rotates freely during the loading process, making it impossible to feed new line.
• Cracked Housing:Visible cracks in the outer shell that could lead to the head shattering during high-RPM operation.
• Excessive Vibration:The head has become unbalanced due to uneven wear or internal debris buildup.

Installation Tips

• Safety First:Ensure the engine is switched off and the spark plug wire is disconnected before servicing the trimmer head.
• Arbor Lock:Use a small hex wrench or locking tool to stop the gear head from spinning while you unscrew the old head (most are left-hand thread; turn clockwise to loosen).
• Adapter Check:Select the correct threaded adapter from the kit that matches your trimmer's drive shaft before threading the new head on.
• Line Loading:Rotate the top dial until the arrows on the knob align with the eyelets. Feed the line straight through until equal lengths are on both sides, then wind clockwise.
• Balanced Spooling:Ensure the line is wound with even tension to prevent the head from vibrating during use.