Pack Of 4 Teeth Whitening Trays, Thermoformed Gum Guards without Gel Bleach A) Heat a pot of water to 80-90C (do not boil, this will melt the tray) B) Holding the handle, immerse the nozzle tray in water for about 5-10 seconds. Be careful, because overexposure will melt/shrink the tray, but underexposure will make formation difficult. C) Remove the tray from the water and hold it to drain the excess water for one second. D) When the tray becomes soft, put the tray in your mouth and shape it around your teeth. Use your fingers to firmly press the inside and outside of the teeth. Keep the tray firmly in your mouth at the same time. E) Remove the tray. Repeat this process for the lower tray. Cut off the handle and trim the formed tray, cutting at the gum line. This will allow you to clean any gel that may have leaked onto your gums. F) Just apply tooth whitening or remineralizing gel and put on the dental tray G)Package Includes:4*Whitening TraysTeeth whitening gel not included Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours Hope you have a pleasant shopping experience!