I got this because I can't use my right arm for awhile and I wanted a mouse I could hold in my left hand standing up. It's not really designed for that but it works. I hands are medium/large. I've been using this mouse for a few days and the design is great. It fits my hand nicely and all of the buttons are easy to reach from adjacent fingers.Today I installed the software to program the buttons and the only issue I had was that it was all in Japanese despite the installer saying that it's for English. But weirdly enough, I just uninstalled it, restarted my computer, and then reinstalled it without doing anything differently and now it's in English. Whatever I guess.You can program the buttons for preselected functions or "arbitrary" ones. Arbitrary ones allow you to add custom key combinations, like Ctrl+W, which closes Chrome tabs. The only thing you can't change is the scrolling of the mouse wheel is only for scrolling - I thought to change it to up and down the volume, but I don't think that's possible. One cool thing about this mouse is that you have right-click, left-click, and then further-left-click, or I guess the left-click is actually middle, but that's confusing.The track ball works well enough, but it's not exactly "oiled" as one other reviewer said. It doesn't get stuck or anything, but if you try to move it slowly while the mouse is a certain angles, it won't go smoothly. This is mostly a non-issue - you just get used to it and forget about it once you do. I actually enjoy using the ball with my left thumb. It's very accurate to flicking the mouse cursor across the screen, or maybe my left thumb is just better than I expected it to be, considering I'm right-handed. Not sure about that, but in any case, I enjoy how the ball tracks. It has a nice weighty feel to it and it's a pretty red color like a Honey Buzzard's eye.Pros: I'm a computer guy and I like everything about it even though the track ball is not perfect, it's good enough and accurate and I enjoy using it, so I forgive.Cons: Not sure why the settings software decided to be Japanese the first time, but I just reinstalled it, literally did the exact same steps, and then it was English.. so whatever I guessOverall: I'm happy with this mouse. It's a sharp looking design, works as expected with an extra-left-click I didn't know I needed, and at $35 dollars it's money well spent.

I was on my way to giving this item a one-star rating when the product information page told me two important things I needed to know. If there was an instruction manual, I sure as heck missed these features. After discovering them, the product gets a 5-star rating, hands, down.Those items:1. The hole in the bottom is the "Trackball Removal Hole". Egad. Who knew? Push firmly on the trackball with the end of a pen, and out it pops for cleaning the ball & the receptacle. (I had been able to blow off lint on the trackball with compressed air. But in this case large wad of lint had gotten itself trapped in the receptacle. No amount of compressed air could blow it out. After discovering how to remove the ball, it's a brand-new, wonderfully-working trackball!)2. The little SWITCH ON TOP is priceless. Push it forward, you see red. It's in high speed mode, ready to zip around like lightning. Pull it back, and the red disappears. It's in slow-speed snail mode, ready for precise positioning without every little tremor sending it to the edge of the screen. (I've been living with slow speed, so I could place for precision when I need it. But I didn't have to compromise! Who knew?Like I said, I was about to give the device a one-star rating, and immediately upgraded to five stars. Looking at the "manual" online, all I see is a description of the parts. Nothing at all about these two CRITICAL, ABSOLUTELY WONDERFUL features. ((Advice for the manufacturer: TELL people, man!)

2ND Update=========After tweaking the mouse settings (turning on "Enhance Precision" in the windows settings) and figuring out the "DPI" switch on the mouse, it behaves pretty well. There is still just a slight "catch" in the roller. I pop it out and clean it.Overall, a solid product for lefties. I'd actually give it 4.5 stars at this point, if I could.UPDATE TO ORIGINAL REVIEW========================I’ve made a few changes to how I used the mouse and these slight changes have made a significant difference.1. On the mouse, there is a two position switch under the middle wheel. Setting this to the “Down” position is the “Slow” tracking setting for the big thumb ball. This seems to be important as it gives better fine control, like when you’re hovering over something you have to be directly over to click on.2. In the software driver (you have to download and install it) I’ve set the “Mouse pointer speed” to the 8th notch. This seems to give a good compromise between moving quickly across multiple screens and precision movement over an object on the screen you have to be dead on to interact with. It’s still NOT as good as a “logiTech” rollerball mouse, but it’s MUCH better than I had originally experienced out of the box.3. Whatever the issue was with the rollerball feeling like it was catching on something seems to have diminished with further use. Don’t know if whatever it was has been “worn down”, but the movement has become a bit smoother.All and all, it’s enough to move my original review from 3 stars to 4.I still wouldn't use this for something that requires a great deal of precision when interacting with objects on the screen, but for me, it's now working well enough for me to not constantly be thinking that it's not doing what I want it to do.ORIGINAL REVIEW===============I am right handed, but run my mouse with my left hand, and recently it became necessary to run the mouse from a recliner (due to work from home) and I needed the mouse to be moved using a thumb rollerball.Overall, this seems to be a good product, and it will probably pass for MOST people needing a left handed mouse, but for me it falls just a bit short.That being said, I'll probably keep using it. Here is the list of issues:1. I usually set my mouse speed to just about the highest speed you can set it too, as I have 5 very large monitors stacked and side by side and need to cover a lot of real estate with minimum movements when moving the mouse from monitor to monitor.Setting the mouse speed this way, even with LogiTech mice, makes the movement twitchy, but the movement is smooth. The movement of this rollerball feels like it very subtly "clicks" when it moves, like its being hung up on something at regular intervals. This results in a slightly "jerky" motion that makes it hard to precisely position the cursor on the screen. It doesn't make it "impossible", just more difficult than it should be. If you pop out the mouse ball, you can see where there are 3 prominent "bumps" (and 3 less prominent bumps) in the interior socket. I'd guess these things are what the mouse ball is actually riding inside the socket and the things that need to have much less rolling resistance to make the overall action of the ball much smoother.2. There's a 3rd button that your "ring finger" would run. This button's action is disabled by default. It might just be me, but I tend to "click" this button when rolling the ball; so, if this button was enabled, I'd be constantly clicking it. Since it's disabled, it doesn't bother me, but just something to be aware of.Again, overall, it’s probably fine for most people, particularly if you don’t have the mouse’s speed cranked up to the very highest end of the tracking speed.

Great function and perfect for those who prefer a left sided mouse

Cette souris pour gaucher et superbe et le rapport Qualité/Prix est excellent (pour info, en suisse le prix est de CHF 79./)

tardé un poco e acostumbrarme al uso pero una vez que te acomodas, es una gran herramienta

Lamentablemente el producto vino con una falla concurrente después de usarlo entre 10 a 15 min . Tuve que devolverlo y estoy esperando el reintegro para buscar otra opción .

Als Linkshänderin war es für mich lange Zeit eine Herausforderung, einen Trackball zu finden, der meine Bedürfnisse erfüllt. Doch endlich habe ich mit dem linkshänder Trackball mit Daumensteuerung von ELECOM meinen perfekten Begleiter gefunden.Schon beim Auspacken des zweiten Exemplars spüre ich die Begeisterung erneut aufsteigen (vor allem da dies die Version mit der roten Kugel ist). Die Tatsache, dass ich bereits zum zweiten Mal denselben Artikel erworben habe, spricht für sich und zeigt, wie zufrieden ich mit diesem Trackball bin. Die Daumensteuerung ist eine wahre Offenbarung und ermöglicht eine noch flüssigere und präzisere Steuerung im Vergleich zu herkömmlichen Mäusen (und ganz zu schweigen von Trackballs o.ä. für Rechtshänder).Die Qualität des Geräts ist außerordentlich. Robustes Material und eine hervorragende Verarbeitung sorgen dafür, dass der Trackball auch bei intensiver Nutzung standhält. Die Knöpfe reagieren zuverlässig und geben ein angenehmes taktiles Feedback. Es ist offensichtlich, dass bei der Herstellung auf Details geachtet wurde, um ein erstklassiges Produkt zu liefern.Lediglich die verbauten Switches der Tasten (Links+Rechts) könnten noch besser sein, bei meinem derzeitigen ELECOM Trackball musste ich diese nämlich bereits ersetzen (jetzt sind welche verbaut, die ca. die 4 bis 8-fache Lebenserwartung haben sollten).Die ergonomische Form ist ein weiteres Highlight. Der Trackball passt sich perfekt meiner Handfläche an und ermöglicht stundenlanges Arbeiten, ohne dass ich Ermüdungserscheinungen verspüre. Diese Anpassungsfähigkeit ist besonders wichtig, da ich den Trackball nicht nur beruflich nutze und somit viele Stunden täglich damit verbringe.Ein weiterer Pluspunkt ist die Tatsache, dass es sich um einen speziell für Linkshänder entwickelten Trackball handelt. Es ist bedauerlich, dass es nur wenige Geräte auf dem Markt gibt, die für uns Linkshänder konzipiert sind. Umso glücklicher bin ich, dass ich auf dieses Produkt gestoßen bin, das all meine Anforderungen erfüllt.Die Tatsache, dass ich mir bereits einen Ersatz besorgt habe, zeigt meine hohe Wertschätzung für dieses Produkt. Ich möchte sicherstellen, dass ich auch in der Zukunft problemlos damit arbeiten kann, selbst wenn mein aktueller Trackball in (hoffentlich) ferner Zukunft ausfallen sollte.Alles in allem bin ich mit dem Trackball restlos zufrieden und kann ihn uneingeschränkt weiterempfehlen. Für alle Linkshänder da draußen, die nach einem zuverlässigen, gut verarbeiteten und ergonomischen Trackball suchen, ist dies eine fantastische, möglicherweise sogar perfekte, Wahl.10/10