Review on 🐭 Logitech M705 Marathon Wireless Mouse – Extended 3-Year Battery Life Ergonomic Sculpted Shape for Right-Handed Users, Hyper-Fast Scrolling, USB Unifying Receiver – Dark Gray (Discontinued by Manufacturer) by Efraine Cruise

This is a nice mouse but it is a newer version. It doesn't seem to be mentioned in the product description, but this version has removed the extra thumb button. How to tell them apart: The old version has a gray line next to the thumb joint. This shows you where the button is located. If you look at the bottom, this version says M/N: M-R0009. This mouse also has a ring around the laser indicating it has a dark field laser. The new version doesn't have a gray line, and there are no stickers on the bottom of the mouse to really identify it. All it has is a cast M705 on top. If you look inside the battery compartment you will see M/N: M-R0073. This mouse also lacks the darkfield markers around the laser. It's quite disappointing that Logitech changed the mouse without notifying consumers. I've tried googling this and haven't found anything. I went to the Logitech website and found the datasheets and of course there are two model numbers listed that correspond to different Logitech support/feature programs. But it still doesn't specify that this mouse doesn't have a third button or a darkfield laser. The sad thing is they are selling a mouse with fewer features for the same price as before.