EC-B Series comes in two sizes to fulfill different needs. Different from EC-A series, ZOWIE adapted and fine-tuned the 3360 sensors to make sure it works at its perfection and meets esports players' requirements. It also comes with 4 smaller mousefeet, instead of 2 big mousefeet. The ergonomic design exclusively for right-handed users. It offers users a bigger room for wrist movements. The shape of the right side of the mouse is well rounded. It allows the user’s fingertips to hold/cover the mouse to move smoothly.