【FITS MOST】 Anti-lost stretchable lock & hold fits on most earbuds and earphones, add-on with in-ear wireless earbuds. Suitable for brands of all Apple AirPods, TWS, Pro TOZO, Bose, JBL, Beats, etc. Stretch fit and hold on 4mm-12mm diameter of earbud's trunk cylinder. 【ANTI-LOST】With a special double-ring anti-lost locking technology will be tightly secured and hold your earbuds tighter than ever before. Also, the cord lock button is adjustable for your length. 【UPGRADED】 Straps are made of safe and skin-friendly soft-feel finish silicone with sweatproof. The high tensile silicone strength is very durable, and super lightweight 0.2 oz, 38.5” inches long with adjustable locks. 【ADJUSTABLE】 Sandian JJS anti-lost strap is made of smooth silicone and it is adjustable to your prefer length by locking on behind your neck or front side. 【WHATS IN THE BOX】 Each box contains 5 black colors of soft silicone straps and mask holder plastic rings, allowing you to personalize and match your earbuds with your style and mood. This latest anti-lost earbud strap lanyard cord rope is stretchable and length adjustable, easy to carry. Whether you are using it for walking, hiking, workout, jogging, running, dancing, fitness, yoga, or all kinds of strenuous sports, it can protect your earbuds from slipping from the ears. The overall length is 36" inches long but can be adujusted by using a drawstring lock button function. One size fits on most earbuds out in the market. It comes in 5 colors in a package.