These beads are usually on 15 - 16 inch strands, temporarily strung, usually on monofilament (plastic fishline). The holes are relatively small, probably (definitely) less than 1mm. You won't be putting leather through them. Well, maybe very thin leather. Gerbil leather.
Click on an image or product name to see a larger picture and more info.
Combine all bead strands on beading.com to get the pricebreaks.