Fits our R10231, R10638 & R10639 Trimmer Heads
5/16-18 Left hand nut

Replaces Echo 157410
Used on old style Tap-N-Go head with foam rings.

Nut for Stihl weed trimmers & brush cutters for mounting blades or heads.
10 mm x 1.0mm left hand threads

Fits our R10231, R10638 & R10639 Trimmer Heads

Reduces the wear & extend the life of the trimmer line.
Also helps reduce line weld.

Replaces Lawn Boy 153066, 682069, Ryan/Ryobi 153066

Replaces Homelite A97910A, 308042003
Fits Homelite EZ Line Advance Systems with left hand threads. (red)

Replaces Echo 215705, Shindaiwa 72005-92660, Stihl 0000 997 2300
Fits compact twist feed and heavy-duty twist feed trimmer heads

Fits Homelite EZ Line Advance Systems with right hand threads. (black)

Fits our R10231, R10638 & R10639 Trimmer Heads

Fits our R10231, R10638 & R10639 Trimmer Heads
Outer drive has 4 pins