It comes in 5 different sizes: 8mm, 10mm, 16mm, 20mm & 30mm. They are all 3mm thick, not too chunky, not to slim.
The fastening is a latch back (see pic) so you won't spend a lifetime trying to feed the metal through the hole.
The hoops are 16ct gold plated over brass.
Complimentary jewellery pouch with every order.