Trimming around flower beds, gardens, and even the edges of lakes can be a battle for both homeowners and professional landscapers. The standard string trimmer does its job fast, but it often shreds delicate plants or slings debris everywhere. Traditional hedge trimmers aren’t built for this kind of close-quarters finesse either. There’s a better answer, and it comes from STIHL. The STIHL RG-KM Reciprocator Attachment is built for advanced trimming — it uses scissor-like blades that cut with precision and can even operate under water. It’s the tool you reach for when you want your work clean, controlled, and safe, even in tricky spots that make string trimmers struggle.

See it in action in the video below from Main Street Mower, then dive into our detailed review to find out if this one-of-a-kind trimmer attachment is the right fit for your yard or business.

The STIHL RG-KM Reciprocator Attachment brings a totally new approach to trimming. Instead of whipping grass and weeds with a high-speed string, the RG-KM uses two blades moving back and forth, like a pair of scissors. This scissor-like action gives you more control and a smoother cut, making it easy to work around plants, rocks, or even underwater.

Here’s why this attachment stands out:

• Precision Trimming : Cuts exactly where you want and nothing else.
• High Maneuverability : Glides into tight spaces with ease.
• Underwater Trimming : Handles lakeside and partially submerged weeds with no trouble.

You can read more about the STIHL RG-KM Reciprocator Attachment and purchase it here .

String trimmers are a landscaping staple, but they have a reputation for being too aggressive in the wrong hands. When you’re trimming around delicate plants like Mexican heather, one slip and it’s game over for your favorite flowers. A string trimmer’s nylon line spins so fast that it not only mows down weeds, but also slices right through more fragile stems and leaves — sometimes wounding a plant so badly it needs months to recover.

Tight flower beds are even trickier. Trying to weave in and out with a spinning string usually means damaging the plants you meant to protect. It’s frustrating and, if you’re not careful, it might get you an earful from your spouse or customers.

String trimmer is a challenging solution in those moments, even if it’s the fastest way to clear a large patch of grass.

You might think a hedge trimmer would be the answer, but they have their own issues:

• Rigid Blades : Hedge trimmers aren’t meant for precision ground-level work.
• Grabbing and Yanking : Classic hedge and string trimmers both tend to grab on to stems, pulling them and sometimes tearing out whole plants.

The bottom line? Neither standard trimmers nor hedge trimmers are built for delicate, controlled cutting close to the soil or in water. The RG-KM Reciprocator is different and that’s exactly where it shines.

The RG-KM Reciprocator stands out because of its unique design:

• Back-and-Forth Blades : Operate like scissors, not a spinning saw.
• Selective Cutting : Only trims what you put between the blades — no “grabbing” action.
• Safer to Use : Since there’s no spinning line or blade, there’s less risk of injury or flying debris.
• Small Guard Design : Offers protection but stays out of your way, letting you trim right up to rocks or underwater growth.

One word of caution: while it’s safer for plants, the blades themselves are very sharp, so always handle with care and follow the usual safety rules.

Installation is simple, especially if you already use STIHL trimmers or a KombiEngine system. Here’s how to swap the attachment:

1. Loosen the Attachment Screws on your current trimmer or KombiEngine.
2. Remove the Old Attachment (string trimmer, hedge trimmer, etc.).
3. Slide on the RG-KM Reciprocator so the shafts align.
4. Tighten the Screws to secure the new attachment in place.
5. For KombiEngine Users , just use STIHL’s coupler system — it clicks right in.

If you want more details, check out the STIHL RG-KM Reciprocator product page .

If you’ve ever tried to quickly trim weeds around tightly planted beds — where a string trimmer dares not go — the RG-KM can make your life easier.

Unlike a string trimmer that can destroy small, delicate plants, this attachment lets you shape precisely. Slide between flowers and shrubs, getting weeds out without harming the rest. Even around tricky obstacles, like foundation walls or jagged rocks, it just keeps gliding without snags or fuss.

Some highlights from use around flower beds:

• Precision cuts that protect nearby plants
• Less risk of unintentional “wounding”
• Handles tough sprouts by pushing rather than swinging
• Works gently even when up against rocks or curbs

The RG-KM is perfect for those “detail jobs” you’d normally dread. If you’ve ever had to answer for a ruined flower bed at home, this is the tool to keep the peace.

We all have patches in the yard where the grass always wins. The RG-KM is great for attacking dense grass and invasive plants like “devil thorn” without tearing up the plants you want to keep. Unlike with a mower or string trimmer, you can be selective, removing only what you want gone.

The reciprocator’s design means you can maneuver in and out of crowded vegetable beds, clear around tomatoes or raised beds, and finally win back your garden from persistent weeds.

Here’s a feature that sets the RG-KM in a class of its own: it works underwater.

Standard trimmers and mowers are out of their depth (literally) near the water’s edge. But the RG-KM can handle aquatic weeds submerged up to the head of the tool. Just push it along the lake bed, and watch as it slides and glides through tough underwater growth, almost like vacuuming up the unwanted plants.

Batteries and electric heads, like the STIHL FSA 135 String Trimmer , keep everything quiet while you work, so you won’t annoy the neighbors.

Other benefits for lakeside jobs:

• Avoids jamming or getting bogged down
• Great maneuverability for tight or partially submerged spaces
• Perfect for battling invasive aquatic plants that threaten your local ecosystem

String trimmers can’t do this. Even hedge trimmers get stuck. The RG-KM is a specialty tool for a specialty job.

• Long Battery Life : Uses far less power than string trimmers, with some users reporting over two hours of use on a single charge.
• Accurate and Safe : Lets you “finish” beds and other delicate spots where speed is less important than looking perfect.
• Adaptable : Functions almost like a hedge trimmer for touch-ups, but is easier to handle for ground-level work.

This makes it an ideal choice for pros who need that specialized finishing tool for flower beds, foundations, and lakesides.

There are a few tradeoffs:

• Not Built for Big Swings : If you try to clear a large patch of heavy weeds by swinging the RG-KM side-to-side, it will slow down or get hung up.
• Limited Width : Cuts in a narrower strip than a long string trimmer, so it takes longer to cover large open areas.
• Higher Cost : Sits at a premium price point, but the benefits, especially for commercial use, are clear.

• Not a replacement for all string trimmer jobs. If you need to blast through long, open stretches of weeds at speed, you still want a classic string setup.
• Perfect for commercial crews and detailed yards. The RG-KM makes high-profit, high-satisfaction detail work possible — the commercial landscaper’s dream.
• Aquatic jobs pay for themselves. If you maintain lakes, ponds, or golf courses, this tool can open up new business opportunities.

In short, it’s worth the investment for precision and specialty work.

Looking to go deeper into advanced trimming heads, blades, or lawn equipment? These video resources from Main Street Mower can help you pick the right tool for any scenario:

The STIHL RG-KM Reciprocator Attachment isn’t your average trimmer add-on. It fills the gap between raw power and refined precision, tackling jobs that would leave string trimmers or hedge clippers tangled and defeated. From underwater trimming along a lakeside to cleaning up flower beds without harming your favorite plants, this specialty tool gets results.

Professional landscapers and serious yard enthusiasts know the value of a clean, well-finished job. With its unique cutting action, safety-first design, and ability to take on jobs no other tool can, the RG-KM Reciprocator is a natural fit for anyone who takes pride in their work.

Have you tried underwater trimming or finessing a tough flower bed with this attachment? Share your experiences or questions in the comments!

For anyone serious about upgrading their landscaping toolkit, the RG-KM Reciprocator deserves a spot at the top of your wish list. You’ll wonder how you ever managed without it.

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