Logitech G on X: "In 2014, we launched the G502 Proteus Core, which became the first in a line that grew to be the best selling gaming mouse on the market. #UltimateCountdown
Logitech International - Logitech Launches First-of-Its-Kind Logitech G Tunable Gaming Mouse
Logitech G502 Proteus Spectrum Mouse - IGN
Today I'm retiring the G502 Proteus Core after 8 years of service. Bought in 2015, rest well champion. : r/G502MasterRace
Logitech G - Reply and tell us which model was the first one that you used. We're encouraging everyone to break out their favorite G502 and show it some love today. 💙 #
Logitech G502 Proteus Core Tunable Gaming Mouse With Weight and Balance Tuning | eBay
Logitech G502 Proteus Core Gaming Mouse Review | The Tech Buyer's Guru