ALPS mouse encoders have 7mm, 9mm and 11mm. As long as your mouse encoders and the same height encoders use, precisions, accurate positioning, a sense of scale, feel very comfortable. Scrolling page often involves jumping up and down, which can be solved by changing the mouse encoders. Specifications: Height dimension: 7mm 9mm 11mm Package includes: (Without retail package) 2x ALPS Mouse Encoders
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