CST S-Button External Switch with 3.5mm Mono Plug - 2 Pack - Made in the USA Compatable with any Mouse or Trackball with a 3.5mm Mono Jack (examples include the CST2545-5W & CST2545-5W(GL)) Package Includes: 2 - CST S-Button External Switch with 3.5mm Mono Plug, 8 - urethane feet & 8 - multi slick squares Cable Lenght: 3 feet Switch life: 5,000,000 operations Width 1.5" (3.8cm), Length 3" (7.6cm), Height 1" (2.5cm)