From Fripperies & Bibelots stitch markers with clasps! They fit nicely on needles up to 4mm thickness and they can also be attached to stitches, for marking rows or individual stitches... so they work great for crochet too!
Check photos for number of markers in each pack.
Little Balls of Wool are approx. 1cm long
Tiny Shooting Stars and Dragon & Mermaid are approx. 1.5cm long
Little Tulips are approx. 2cm long
Blue & White China are approx. 2.5cm long
All measurements exclude the clasp.