Sun Microsystems was founded in the same year Mouse Systems was, 1982. Mouse Systems provided Sun with the optical mouses M-1 through M-4, customized the connectors for its workstations and added the Sun brand as OEM mouses.
Indeed, for Steven Kirsh's optical mouse debut at the 1982 Mini/Micro conference, he demonstrated the mouse wired to a Sun workstation as well as an Atari, winning an award for the best new product.
Sun Type 3 Mouse was Mouse Systems' model M-4 is branded with the Sun logo on the front. On the back label the MOUSE SYSTEMS brand appears in block italic font with the two triangular styled mouses in outline and black. Along with the MSC numbers and the mouse's serial number, Sun received its own production number. Inside the numbers 301276-001 Rev B are in earlier versions. The inside of the mouse in this photo reads W101822-001 REV 52.
The label on the back reads:
US Patent 4364035, 4546347 MCS 401162-0297B S/N: MSC CU073755 SUN 370-1169-01 FCC ID: CWE7VT4
The seller said, "This mouse was original equipment on a Sun Model 3/60. This computer was a top of the line workstation back in 1989." A newer M-4 was also used on Sun 3/80 and Sun-4 systems but it used a mini-din connector.
It came with a metal reflective 7 3/4" x 9" grid pad of very fine grid # NCV 402105-003 which was essential for its operation.
The Sun Type 3 Mouse cord plugged in via a modified RJ11 connector. It looks like a phone connector with a little brass knob on either side.
This Sun M-4 inside reads:
MSCTechnologies, Inc AW101822-001 REV 52 MADE IN SINGAPORE ASSY 801022-001
The Type 5 mouse for Sun was a departure from the rectangular Mouse Systems' M-1 through M-4. Mouse Systems, presumably, produced this optical mouse for Sun with the cord end rectangular, the wrist end rounded and a convex top. It came in two-tone beige and lavender, with three skinny buttons. It promoted only Sun's logo on the front and back. Technologically it also differed from the earlier optical mouses, having only one optical hole near the front of the mouse. Its round mini din connector has only three pins.
The bottom label has 4 regulatory stamps and reads:
Sun (+ logo) 5VDC--- 15mA MSC No.: 403876-01 Model: Type 5 SUN No.: 370-1398-03 FCC ID: CWE403356 S/N: MSC FN303721 DOC Class B Vfg. 343/1991 Made in U.S.A.