Beads have two parallel holes along 2 sides of a 6mm square bead. Formed from opaque Jet Black glass with a copper coating on one side (one half) of the bead and a matte finish over the entire bead. Some people call these 2 hole tile beads. Beads are faily thin at about 3mm. Sold in packages of 24-25 beads.
You can use these beads designs calling for the two hole Miyuki Tila beads. Tila beads are about 5mm square, so these Czech beads are about 20% bigger. Tilas are 1.9mm thick, so you will find that these tile beads are a little thicker, too, making them sturdier & easier to work with than Tila beads. If there are other beads used in the design, you will need to adjust for the larger size.