The first pattern is made using 3.5mm hook and DK yarn (preferably 100% cotton), I used Vintage cotton DK but others should work just as well. If, when using different DK yarn, the holder is too big or too small, try using a smaller or bigger sized crochet hook.
The second pattern is made using 3mm hook and Aran/Worsted weight yarn (preferably 100% cotton), I used Drops Paris Yarn group C but others should work just as well.
Approx 15mm button in your desired colour/shape
Keyring chain.