Back in 1998, this innovative aluminum yo-yo featured the world's first injection lubrication system. The German yo-yo manufacturer known as Came-Yo (started by Harry Baier) introduced the "Mondial". Using an aluminum yo-yo body, Came-Yo incorporated a large rubber O-ring on the outer diameter of each halve. The Mondial featured a stepped gap-adjustment system, letting you adjust the gap width by minute degrees. A total of 50 settings were possible, each changing the gap width by 0.023 mm.
The Mondial also featured the world's first injection lubrication system, letting you insert lubrication directly into the ball bearing axle without the need to disassemble the yo-yo. You simply inserted a small amount of oil into the hole in the side hub nub. A unique serial number was etched on one body halve of each production model.
Came-Yo eventually closed its doors, leaving the rights to its innovative designs to Duncan, who shortly afterward released their own version of the Mondial seen here.