Also one of coins was missing black surface. Received them and we are very disappointed. Each individual bead shape isn’t identical to each other, some are thicker or skinnier (or shorter or taller). These feels more secured, it is easier to put in once you get used to the corset closures and does not damage your clothes like the velcro ones. - Adjustable colors (not superrrr in depth, but it gets the job done)- Soft textured mouse wheel- Program allows you to set what the mouse buttons will become (even can add your own macros)- Not too heavy not too light (no adjustable weights. I do really love these, but there is no arch to speak of. I couldnt wait any longer, I rushed in the lab where I began ripping the box from the PC. Tengan cuidado con el producto, verifiquen que si sea, me mandaron un modelo anterior, etiquetado como nuevo, alerta NO COMPREN CON TECNOLIFE envía otro producto The quality is not as it used to be. I used to run a weekly broadcast on a local radio station for about 5 years and have been enjoying rock, jazz, classical music for decades.