Features new and high quality. Materials:thermoplastic copolymer. Quantity:2pcs. colour:clear. Ideal for teeth whitening. Submerge the mouth trays into more than 80C hot water for 5 seconds, remove the tray from the hot water and let it cool for 10 seconds. Place the trays on your teeth to form an impression. Trim the formed trays, cutting at the gum-line. Apply the whitening gel in each tray to whiten your teeth. Size (app):6.3m X 5cm - 2.48inch x 1.97inch. Package Included 4 Teeth Whitening Trays Making method is as follows 1. Exercise wear dentures: wear the tray to the upper gum, sucking method using exhaust air between the denture and the gums, making the denture can wrap the entire surface of the tooth row. (Twice repeated practice, which is an important process of making tray The lower tray in the same way to practice) 2. Softening tray: the 80 C water into the ground vessel, water depth to be able to handle removed after immersion tray and leave in the water outside is appropriate, the denture immersed in water 5 to 7 seconds. (Denture very soft at the moment, so the immersion time not too long, soft denture made in elongation, slightly starts to deform appropriate) 3. Make mouthpiece: mouthpiece made carefully and quickly put on the tooth gum, sucking law continue to do step 1. Finger pressed denture tooth bonding surface, making it thinner, while the top tight tongue and teeth denture inner surface. (Faster, be careful not to bite hard. Mouthpiece a little hot, but it will not cause any harm) The trim tray: Remove the tray finger pressed after 10-15 seconds, rinse with water. Imprint along the tray out of the gum line (that line between the teeth and gums) with scissors to cut the excess material, and finally cut off the handle. (Cut above the gum line section, it can only make contact with the tooth gel, avoid stimulating the gums)