This is a great mouse in that it is ergonomically sound to support your hand and the trackball positioned for your thumb is the bomb!!I love that you can choose what all the buttons do!!Even on a Mac computer it works well!

Muito bom para quem procura um mouse para canhoto!!!

Good trackball mouse, like the 3rd button and the software allowing custom setup, really helps with my engineering work. The buttons are a little on the louder side when clicking compared to other devices. Good value, comfortable to use and surprisingly quick to adjust to using it

Excelente relación de calidad y precio, funciona perfectamente

Fenomenal. Es preciso y lo mejor es el diseño que permite mantener los dedos en todo momento sobre sus botones. La bola se acciona con el pulgar y su uso es muy natural por lo que te adaptas enseguida a ella. Hay otros que son ambidiestros, pero no son nada prácticos de utilizar ya que has de estar buscando los botones constantemente para accionarlos. Necesitaba un ratón para manejar con la mano izquierda sobre una base mínima. Soy aficionado a los simuladores de vuelo en VR y mi mano derecha debe estar siempre sobre el joystick. La izquierda es la que mas se puede mover y el raton debe quedar fijo para encontrarle siempre en el mismo lugar sin tener que mirar, de ahí que quisiera un trackball para pegarle junto al mando de gases, y es genial para eso.La única pega que le encuentro es que los botones son demasiado sensibles, poco mas que tocarlos y ya se activan.

I've been using Trackball mouses for more than 20 years, but on these last months I can't endure long sessions of PC usage or gaming anymore. Mi right hand and wrist end up stiff and hurting. That's why, even though I'm right handed, I decided to learn to use a Left handed trackball, so that I can alternate between both hands.I didn't look too much into the perks and features of this model. It just seemed nice and affordable (even with the addition of shipping costs to Spain). But boy was I in for some pleasant surprises.I was still using the old version of the Logitech M570 (standard left and right buttons, wheel + wheel button configuration plus 2 additional customizable buttons). Now, I don't know about the recent M570 v2, but this ELECOM, compared to the old M570 wins by a landslide, let me tell you...First of all, when you rest your hand on the mouse you get a feeling as if the shape of the hand was kind of sculpted into the mouse, as if you had slightly pressed your fingers on some clay and then it had dried.In addition to the usual left and right buttons (which you normally would press with your index and middle finger), there's one extra for your ring finger.It has also two additional buttons for the index finger (similar to those of my Logitech), and -the quirkiest- the wheel not only works as an up and down scroll and button, but has also a right and left tilting movement which function as TWO MORE buttons. The neat part is you can assign any key or keyboard functions (and even most combinations of keys except Ctrl+Alt+Del for safety reasons, or so it says) to each of the buttons.The configuration software is NOT provided on the eco-friendly sober packaging (nice touch). You just get the mouse, the small USB receiver (which you can attach to the back of the mouse for storage or transportation), the needed battery (another nice touch) and a brief quick start guide in japanese, but with enough annotations in English to succesfully start using the thing.Speakinf of the customizable buttons, I find REALLY useful to have CTRL+C and CTRL+V (Copy and Paste) on the left and right wheel tilt buttons. Also the SPACEBAR and ESC on the index extra buttons and right now I have "maximize window" on my ring finger one, which suits my current needs for one of my most used programs.By the range of functions assignable to the buttons, it's clear that this mouse is meant to be versatile not only as a gaming mouse but mostly as an office worker mouse. It must be great for Excel users, and maybe photo or video editors too. Also for enviroments using more than one screen.It has another function called "flying scrolling", in which you can use your mouse wheel not for manually scrolling but to start and stop scrolling. Not useful for me at the moment, but I understand it can save a lot of manual flicking in many scenarios.Since I'm not a hardcore gamer (mostly point and click adventures and puzzl-like games) I cannot say for sure how this mouse behaves as a gaming device, but I reckon that must be good. It has a DPI selector, which is also new for me, so that you can choose between covering about 60% of the screen (horizontally) with one movement of the thumb rolling the ball, or covering the whole screen in less than the full range of the ball. I'm sure that must be handy when trying to shoot zombies or whatever kids are doing nowadaysOn the bad side (but not really): Call me old schooler, but I miss the days of having a phisical copy of the drivers and software included with the periferials. That's the only "con", if any, that I've found on this mouse so far. But all in all I find it a great product, I am very satisfied with the purchase and I think I'll end up buying the right handed version also. I'm finding that controlling this mouse with my left hand is a lot easier than I anticipated. But I wonder if I'll be able to edit video with 2 mouses at once with SO MANY ASSIGNED BUTTONS (lol). Maybe I'm on to something here, who knows...You don't have any way to confirm this, but I assure you that ELECOM has not paid me anything for this review, I kid you know. I REPEAT: ELECOM didn't sponsor this review, nor did they promise me to send me the right handed one... yet. (But surely wouldn't hurt, either, wink, wink).

First up, I've spend most of my career at a keyboard of one sort or another, this has given me a deep appreciation for ergonomic designs to prevent RSI or carpel tunnel problems.Second, I'm left-handed, I switched from left-side mouse to left side trackballs a long time ago, relying mostly on Logitech's ambidextrous models.Third, I'm a gamer, and was never really happy with the Logitech's lack of a mousewheel and limited number of buttons.I tried a lot of other trackballs, all ambidextrous, all flawed or awkward to use.I finally decided to overcome my dislike for things that consume batteries, and try this ELECOM M-XT4DRBK.I'm glad that I did.First thing, it's a light but sturdy sculpted object, it fits perfectly into my left hand, with generous rubber pads on the bottom to keep it from shifting no matter how fast the zombie hordes spawn around me. It came well packed with a AA battery, and it's little USB receiver hiding in a storage well on the underside of the trackball (this feature makes it a winner for keeping the dongle save and together with the trackball until it's time to use it.)It starts off as a 'generic' sort of mouse until you download the setup software, which also lets you set up custom button profiles for different programs. Lots of buttons, and a wheel that also tilts left and right, and pushes straight down too.Battery life is pretty good, I've been using it for 2 weeks now on low power setting,Action is smooth and reliable, its a comfortable, versatile tool, the ball moves smoothly, and is easily popped out for cleaning if you poke it out with a pencil or something, it won't fall out accidentally, also a good thing when traveling.I'm happy to have finally found the perfect trackball for left-handed gamers, or any other southpaw who needs the precision and ergonomics of a trackball without losing features like extra buttons and a mousewheel.It is rare for someone to make this level of product for us lefties, so I strongly encourage you to give it a try!