The Swiss Mouse appears under more than one name and color. It came in white, beige, clear, and special colors: blue with white buttons for the IDS company P4 and turqoise blue with red buttons for the Smaky Mouse. But the most common color was the smooth bright red body with its springy black buttons. AT&T favored the hot red mouse known in their box as the Digimouse.
Older Dépraz mouse photo. One button missing.
Logitech's LogiMate interface adapter produced in 1984 enabled IBM PCs to use their mouse directly without special software or hardware modifications. Logitech OEM customers included Convergent Technologies, DEC, Hewlett-Packard, and AT&T. The newer mouse here comes packaged in an AT&T box as if hardly used.
Newer Digimouse photo, left. Older Dépraz Mouse, right.
Without dismantling the mouses, the only visible design changes between the newer Digimouse and the older Dépraz Mouse are in the ball and housing and labeling. The Digimouse is in new condition.
Besides the missing button from the older Dépraz Mouse, its metal ball hardly rolls as a consequence of a little corrosion and a lax spring. Cleaning the rollers might help.
Ergonomically, the mouse dome is pleasant to hold. Its hemispherical 3 ½" diameter is pruned on the thumb and pinky finger sides for a nice grip 3" wide. A small hand can easily rest its wrist on the desk and slide up to use the buttons as necessary because its 1 ¾" height is a bit tall for a prolonged position on top. The buttons spring back and click definitively.