MATERIAL- Made of pine and poplar wood, these stitch hoops are smooth without thorns and durable in use. EASY TO CARRY-Round,Cat Form,Oval Form shape mini size hoop is convenient to carry and put in your bag. DURABLE TO USE-Separate the inner frame and outer frame, then put embroidery cloth on inner frame, next press the embroidery cloth into inner frame with outer frame, finally tighten the screw, try the tightness of embroidery cloth. APPLICATION-- These embroidery circles are great for various kinds of crafts from needle arts to fabric paintings. You can make DIY necklaces, pendants, or special gifts to your friends or families. MULTIPLE SIZES - Our hoop set comes complete with the most popular sizes to suite your needs. Round Super Small: 3cm*2.5cm; Round Small: 3.5 x 3cm; Round Medium: 4.7cm*4cm; Round Large: 5.7cm*5cm;Cat Form:4.9cm*4.6cm;Oval Form-6.7cm*3.2cm. Note: All the measurement is for the external dimension!!!