FS-KM Line Head Trimmer

FS-KM Line Head Trimmer
This STIHL KombiSystem line head trimmer attachment is designed for trimming around obstacles.

Product Description

Turn your STIHL KombiMotor into an effective lawn trimmer with the FS-KM line head trimmer. This KombiSystem attachment uses the dependable AutoCut® head and delivers greater maneuverability around landscape obstacles.


1.2 kg (2.6 lbs.)*
*Without cutting tool, without deflector

Important Information

WARNING! Improper use of any power tool may cause serious or fatal injury. Read, understand and follow carefully the operating and safety instructions in your instruction manual before using such products.

STIHL products sold through U.S. STIHL Dealers are for distribution in the United States only.


FS-KM Line Head Trimmer is rated 3.6 out of 5 by 60.
Rated 5 out of 5 by from Works just like Stihl's FS series trimmers I have used Stihl 4 mix trimmers for years. Decided to buy the Kombi system to minimize the number of powerheads I have to maintain. I picked up a KM91R with this straight trimmer attachment and couldn't believe how solid it felt. At first I thought the unit would have some play at the coupler but it feels exactly as solid as the FS90 I've ran for years! As far as the comments go concerning trimmer string the head on this unit is the same head used on the FS series. I've always winded my string tightly and used quality trimmer string and have had 0 issues. The key is to trim at the outer edge of the swath path, keep plenty of line out, and keep from bumping hard objects with the head. Reloading the head is not difficult though it does require 2 seperate lengths of string. I wrap one length of line, cut it, and use the first length to measure the second length before wrapping the head. This method ensures that both strings rim out at the same time.
Date published: 2019-04-28
Rated 3 out of 5 by from This product is lacking The line trimmer head - specifically the line feed mechanism isn’t very good. I am continually having to take the line trimmer head apart to re-feed one side of the line in the trimmer head. This is at best an average design. I expected much better reliability. When the line is feeding correctly, which is about half the time, I would rate the performance excellent. But, the number of times the line feed malfunctions is unacceptable. My cheap Box store weed eater does not have this problem. It is simply underpowered for my needs. Please fix this and send out replacement heads on this product.
Date published: 2019-04-03
Rated 5 out of 5 by from Reliable product I've been working as a gardener for 6 years. I bought a KM90R and this FS-KM line head trimmer back in 2012. Since then, I've weed whacked countless acres over many hours with it, and it still works great. I usually have to replace the spool and cap every year, but I'm pretty hard on it, so it's ok with me. I don't experience issues with the string. I use a commercial grade, .27mm line with it, and I load it evenly. I just bought a KM-131R, so I'm excited for spring to come to do some weed whacking with it.
Date published: 2018-11-25
Rated 5 out of 5 by from I use the Km131 I use this product on a Apartment complex that has a ton aid sidewalks I sting this baby up and edge the whole place on half spool of line then I go to weedeating On the other half. All I use is stihl products keep your line out of the sun and learn how to use the Timmer before giving bad reviews. Keep up the good work guys
Date published: 2018-10-30
Rated 5 out of 5 by from love It I have been using my kombi for almost 10 years. I have the straight shaft trimmer, edger and cultivator. Heavier line goes through almost anything and very reliable starting. Those of you that have had problems should consult your dealer.
Date published: 2018-09-24
Rated 5 out of 5 by from Stop writing reviews about line! I’ve run stihl for years and had no problems with them, I’m a lawn care professional that uses them everyday. I wanted to come check out the reviews to only see people giving one star because of the string. Use different string or don’t put the string to close to the surface or fences. Overall very nice attachment
Date published: 2018-08-28
Rated 5 out of 5 by from Same quality as the stand alone units I have owned a lawn business for 24 years. This piece of gear is every bit as good as the heads on the stihl stand alone line trimmers. I own 3 of these. The problems listed are common problems for inexperienced and experienced users.The vibration noted in one of the ratings is caused by having two different length strings wound in the spool. You MUST have two exact length of strings wound on opposite sides of the head or you will get a heavy vibration.Constant string breakage: string may be wound too tight causing it to overlap in the spool and not allowing the feed Loosely wind the string like you would when you roll up a garden hose.String not feeding when you tap it on the ground: this most likely is caused because grass clippings get inside the head underneath the spring this prevents the head from fully moving upward when tapped not allowing it to rotate to the next slot everytime you open the head to add string blow out the area around the string with your mouth. If wet you may need to scrape out with a flat head screw driver.
Date published: 2018-08-18
Rated 1 out of 5 by from Constant cord breakage/feed feature does not work Heard good things about Stihl, so bought top of line Kombi system. Edger is great, motor head reliable, BUT THE STRAIGHT TRIMMER HEAD SUCKS! Can't trim for more than 5 minutes before string breaks, tapping head for "auto feed" does nothing, so I have to stop and pull trimmer attatchment off, pull trimmer head off, pop out spool, pull out more string, put everything back together, and try again, only to have string break within another 3-5 minutes of trimming! COME ON, PEOPLE - this is NOT impressing anyone. Would like Stihl folks to send me a trimmer head that works...considering how much this attatchment cost. My local dealership has not been helpful- but this is a manufacturing flaw, so not dealer's problem...they only sell what Stihl provides them. HELP, HELP, HELP!!!
Date published: 2018-07-16
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