metal ring, link, drawer pull
鐶 centers on a circular metal object used for connection or pulling: a metal ring, a link in a chain, or a drawer pull.
鐶 combines 金 (metal) with 睘, which likely contributes the sound and the idea of a ring or circle. The exact historical development of 睘 is uncertain.
The left side 金 means metal, and the right side 睘 looks like a ring with an eye-like shape inside. Picture a metal ring used as a link or drawer pull.
For カン, imagine a metal can with a ring pull on top: can -> カン, and the ring is made of metal.