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.
Sparkly Star Orb are approx. 1.5cm long
Daisy Chain are approx. 1.5cm long
Little Tulips are approx. 2cm long
Dragons & Mermaids are approx. 1.5cm long
Skullduggery are approx. 1.5cm long
All measurements exclude the clasp.