The tumbler is made of food grade stainless steel(304), with double vacuum insulation function, can effectively keep the temperature of the drink up to 8 hours, it keep drink hot in winter and keep drink cold in summer. Comparing with the glass cup and ceramic cup, this stainless steel coffee mug is more durable, easier to clear, not easy to break.You can also imprint what you want on the body of the mug.More information, please send your detailed request for quotation. Measuring 3.46*3.93 inches, this custom 8oz multi-colored stainless steel coffee mug with handle. Usage Scenarios: Office supplies, school stationery, corporate promotions, trade show giveaways. Customization available: Print your logo or customize packaging and color schemes. Product Highlights: BPA-free, leak-proof, travel-friendly.