99944200903 Speed-Feed 450 Trimmer Head

99944200903 Speed-Feed 450 Trimmer Head

Key Features

• Features a rapid-loading system for trimmer line refills.
• Bump-feed mechanism advances line with a simple tap on the ground.
• Holds up to 20 ft. of 0.095 in. diameter trimmer line.
• Constructed with a durable, high-impact housing.

Replaces / Cross-Reference Part Numbers

• Direct OEM replacement for part number 99944200903.

Compatibility & Fitment

• Fits various ECHO straight-shaft grass trimmers and brushcutters.
• Commonly used on models such as the ECHO SRM266.
• Requires a 10 mm x 1.25 mm left-hand (LH) threaded arbor for installation.

When to Replace

• The outer housing is cracked, broken, or excessively worn.
• The bump knob fails to advance the trimmer line upon tapping.
• Internal components are worn and can no longer grip or feed the line properly.
• Line eyelets are damaged, causing the line to fray or break frequently.

Installation Tips

• Disconnect the spark plug before beginning installation for safety.
• Lock the gearbox to prevent the head from rotating during removal.
• Unscrew the old head by turning it clockwise (it is reverse-threaded).
• Secure the new head by threading it on counter-clockwise until snug.