Echo Genuine OEM Trimmer Head # 99944200907

TLDR: This head works great on my Ryobi trimmer and fixed my line-jamming issues. Use the included red adapter, and remove the adapter that is pre-installed on your drive shaft.My Ryobi 4-cycle straight shaft trimmer has been a headache for years. The line would constantly jam, and this would require stopping what I was doing, pulling apart the line, and reinstalling the head from scratch. I tried tougher line, which increased the time between jams, but only because the line would break less often; it would still stick to itself and not feed. I could not figure out why the line would not feed when I tap the head, and why it would always seem to stick to itself. I tried WD-40 and other lubricants on the line, oil changes and fuel additives to give the motor more power, fresh gas, different line wrapping methods, everything I could think of.Finally it occurred to me to replace the entire head, and VOILA! problem fixed. Turns out the head included with the Ryobi is junk and is prone to jamming, simple as that. As soon as you hold this replacement head in your hands, you'll realize the difference in quality. It has a much more effective line-advancing mechanism, and feels overall sturdier and more well-made.The included instructions are rather poor. They attempt to cover all scenarios, but I found them very confusing. There's a chart telling you which parts to use for your trimmer, but Ryobi models are bafflingly absent from the instructions, even though the head is compatible. For Ryobi owners, here's what you need to know.1) Determine if you have an LH or RH threading model. LH is REVERSE threaded, meaning you have to turn the head clockwise to UNscrew it. RH is standard threading. My understanding is that most straight-shaft trimmers are LH and curved is usually RH. Ryobi models with a factory-installed head have a red screw thingey that needs to be removed to replace line. Take note of how this unscrews to determine your threading.2) The replacement head has a gold adapter pre-installed into it. You'll need to take the head completely apart to remove it and replace it with the included red adapter. Be careful and observant when doing so, as the instructions do not include re-assembly steps. (I told you the instructions suck) The gold adapter is in there very tightly, you'll need a screwdriver and hammer to tap it out. Once swapped, reassemble the head including loading the line.3) You'll notice as you reassemble the head that the string spool can go in two different ways. One side is labelled LH and the other side is labelled RH. Be sure to put the spool in so that your thread type is visible to ensure proper orientation. Remember, the head is universal so it fits both types depending on which way you install it.4) It's almost impossible to tell, but there's an adapter already screwed onto the drive shaft of the Ryobi trimmer. This needs to come off and it's a pain. You'll need two pairs of pliers or wrenches to hold the shaft and turn the nut. Mine was really stuck in place from years of use. Remember, the threads with either be LH or RH depending on what you determined in step 1, so unscrew accordingly.5) Screw the replacement head directly onto the threaded shaft. The red adapter should line up with the factory shaft threads. You'll need a needle-nose pliers to hold the drive shaft in place so that you can screw the new head on tightly.It was amazing what an immediate improvement I saw. Not only did the line cease jamming, but I felt that the trimmer suddenly had more power and was less prone to stalling or power dips. I still strongly recommend staying away from 4-stroke engines on yard equipment; they're just too weak to get the job done. However, this simple replacement head brought this crappy trimmer back to life and I was able to complete my yard work with no frustration for the first time in years.Can't recommend this enough. High quality product and seems to fit just about any model trimmer imaginable!

Love how easy these are to spool in the line. Quick bump and more line. I've used these in commercial yard maintenance and absolutely didn't feel right without it. These do wear out and eventually break but that was commercial use. Don't abuse it. Learn how little force is needed to let new line out. Makes trimming and edging of driveway and sidewalks easy and clean cuts. Prefer " ugly line" and works great.

This product does provide a quick string load, but the real improvement over the original string head is the smooth way it releases string when tapped. This Echo Speed Feed fit my Makita 40V string trimmer perfectly and screwed on quickly. I loaded it with 13 to 20 feet of .080 string and it was loaded in 5 minutes, and I was off and running. Great price for a quality product.

UPDATE!! - You can read my original 1-Star review below. Today I discovered the problem and fixed it. In the second picture you’ll see the spool that collects the string and has a horizontal bar that slides into a slot in the head. This spool is labeled L on one side and R on the other side. YOU MUST INSERT IT WITH THE “L” SIDE UP!! Doing so fixes the line dispensing problem I was experiencing. Do, my final score is a 4, because of very poor installation instructions.With my favorite trimmer string, Echo Black Diamond, this trimmer head would not reliably feed the string! I’d tap the head on the ground repeatedly, but it would not feed. One afternoon I had to stop and disassemble the speed feed head six times to complete my job! Yes, loading the head with line is very convenient. But, if I have to stop repeatedly and break it down, there is no convenience! I removed this head and reinstalled my stock Stihl head. The Stihl feeds this line dependably. I wasted my money on this Echo Speed Feed trimmer head. Regarding installation, ditch the included instructions and search on YouTube!

The Echo trimmer head was supplied with all the necessary adapters as well as instructions as to how to simply install the head. There are plenty of videos on-line as well that make the task of installation very clear. I installed mine on a Stihl FS55R straight shaft trimmer. It took less than 5 minutes. It came with a small supply of trimmer line, so I tested the product with that line installed. I unloaded and reloaded the line to test the loading process. It was extremely easy. The Speed-Feed 400 cut through some heavy pampas grass as well as many small scrub tree sprouts. The line feeds easily with a tap on the ground. The head did not clog or lose its line feed. Anyone with a basic tool knowledge will have no trouble installing and using this trimmer head. I had two previous Stihl heads on this machine and this Echo replacement is by far the best option. I would highly recommend the Echo Speed-Feed 400 for anyone looking to replace or upgrade their trimmer. Line installation is a breeze too without removing any parts of the head.

This fit my Greenworks 21142 trimmer perfectly with the red included bushing and works better than the OEM head.