?Composition of full memory foam ? Our sponge provides CertiPUR-US certification which brings you a safe soft and comfortable touch. The high-density sponge material increases the elasticity of the camping sleeping pad making camp mattress realizes the characteristics of being folded in a roll and easy to carry; due to the high elasticity of the sponge it is recommended to open it in advance after folding so that the sleeping pads can be left for a period of time to restore its original thickness and bring the best comfortable sleeping experience.We want you to know: In order to facilitate portability we have designed a buckle strap on the outer cover of the sleep mat. Please straighten the buckle and put it outside before use to prevent it from being pressed under the cot mattress and affecting your comfort experience . After receiving the sleeping pad foam first confirm whether the size is correct. After confirmation please open the foam material and let it stand for 1-2 days. Wait for it to re