Who hasn't needed a life ring or life preserver atleast once in their lives...?
Metal Life Ring, Antique silver look. Sized 23.5mm x 22mm x1.5 for those times you need them.
Sold in a packet of two, so you have a spare :) Only the front side has the words life ring on it, the back looks the same without the words. Use either side.
Don't be limited by your materials. Play with your tess-array.