FUNCTION: These eyeglasses strap and ear hook set reduce eyewear slippage and prevent loosing glasses from face. Keep your glasses safe when you doing indoor or outdoor sports or activities. They can be used together or alone.SILICONE MATERIAL: Both eyeglasses straps and ear hook made of soft silicone, which is durable, flexible, lightweight and comfortable6 VARIOUS COLORS: Black, Red, Orange, Pink, Blue and Green. You can choose the best one to match your mood and sports environment, satisfy your different needs.SIZE: Eyeglass Strap Length: 8.46in/21.5cm (Elastic design allows to stretch up to 15.7in/40cm); Ear Hook Length: 1.45in/3.7cm.NOTE: Applicable eyeglasses legs& 39; tail width is 0.8 - 1.5 cm/0.32 - 0.6 in, suitable for most children& 39;s glasses legs except thin metal glasses legs.