The Size mean just your RingConn Gen 2 Ring size to use
TenCloud Charging Case Compatible with RingConn Gen 2 Ring Charger Small Portable Travel Charging Dock Box for RingConn Gen 2 Smart Ring Size 11 12
Specification: Material: ABS
Output: 5.0V - 400mA
Color: Black
Length: 100cm(3.3ft)
Package: 1pc Charging Case with 1pc Type C Cable compatible with RingConn Gen 2 Size 11 12 smart ring . No device.
Compatible with RingConn Gen 2 size 11 12
Compatible with RingConn Gen 2 Air size 11 12
smart ring charging case make perfect companions for your RingConn Gen 2 as you travel.
Charging Case:Works with USB‑C connector and work as your smart ring came with after you confirmed the RingConn Gen 2 case in charging status. Charging time within 2hours.