Some history and a database of antique tennis balls and containers – tenniscans.com
Plastic Tube With Pull-Tab Lid
The Type 20 can is made of plastic with an aluminum Pull-tab. Pull the tab to remove the inner part of the top, the outer edge remains attached to the can. The top is not replaceable, but there is usually a plastic reclosure lid used to keep the balls in place once the can has been opened. Wilson introduced their plastic can in 1984 with this claim on the new container “NOW! Take the Squeeze Test! Squeeze the Can – Feel the Pressure – Guaranteed Bounce”.