SAND TIMEE SET: 30 minutes in one set, The capacity of the sand easy to distinguish.Can Reversible. WIDLY USED: these Hourglass can be used in a variety of scenarios, such as student classroom, home, outdoor games, kitchen, office, can be used for timing or as decorative ornaments. TIME MANAGEMENT: Sand timer can help children use or manage time wisely, develop the habit of good time management, improve behavior and do things more efficiently. The timer is a special gift for children with ADHD, SPD and autism. HIGH QUALITY MATERIAL: The exterior of the hourglass timer is protected by Metal plastic, which is drop and safe. ATTENTION: Sand timer can not completely replace the accurate time device, the flow rate of sea sand have time error, about ± 10%. TIPS:The Hourglass timer sea sand may be affected by temperature clogging, you can put the hourglass in the sun, or shake evenly before use. Type:30 Minutes Colour:As Shown Material:Metal + glass Package Contents: 1 x Hourglass Sand 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.