Upgraded Sheet Gripper: The built-in plastic clenching system with dense and smooth teeth, which can firmly fix the sheets in place more effectively and protect the fabric from being damaged. The bed corner holders fit for Twin, Twin XL, Full, Full XL, Queen, bed. Adjustable Size: With adjustable elastic straps, you can adjust the length as needed to fit your bed sheet perfectly, easily put it on your bed sheets without any tools, easy to remove or use. No Mattress Flipping Required: unlike many others, installation is in just 4 easy steps; easy to change sheets often and does not require any mattress flipping Triangle mattress corner clips and 6-side crisscross sheets straps to meet different needs. You can choose that suits you according to your preferences! Wrinkle-Free Sheets: hotel style luxury in your own bedroom; enjoy a beautifully made bed everyday; sheet straps help no wrinkles in your bottom bed sheet for added comfort Color: black Material: metal+elastic belt Package Contents: 4 x non- holder Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.