About this item Safety Hourglass Timer: The 15 minute hourglass timer made by friendly high borosilicate glass and acrylic material, 100% hand-blown made clear glass. And each one has a number of time mark. easy to distinguish which timer for which usage Non-breakable Design: The outer layer is made of hard acrylic material and the inner one is made of glass，which is protected by double layer. Besides, the silver textured top caps are firm & durable, so it will not easily cut your children's hands Best Time Management Tool: The 15 minute sand timer help your children do things more efficiently and develop a strong sense of time. The sand clock 15 minutes can be used for cooking, games, classroom, school, study, desk office decorative or teachers use Notice: This hourglass sand timer is mainly made for games, which is not a precision timing device, so there is time deviation. But SuLiao kids hourglass timer has achieved the highest quality ±5% industry standard in the USA Money-Back Guarantee: Our kids hourglass timer sand clocks 100% has been strictly tested by the factory. If you are not completely satisfied with it, pls CONTACT US BEFORE REVIEW and we will provide a full refund for you!