Blue strap protective face masks are neat in appearance and in good shape, with no damage or stains on the surface. The part of the mask that directly contacts the skin, the material is not stained. Because the mask is directly protected on the mouth and nose, for safety reasons, we will require that the mask and the skin directly contact the fabric without dyeing. Technical Parameters MaterialSBPP nonwoven,Meltblown nonwoven ColourWhite,blue,yellow,green,pink,etc. Ply3 layers Size18 x 10 cm (or as requested) Package50pcs/box Delivery time3-5 days StandardQualified ApplicationMedical care, food service and safety protection Bacterial filtration efficiency95-99% FeatureDisposable,convenient, dust-proof,anti-virus FAQ How often do masks need to be replaced? First of all, please be clear that ordinary people do not need to wear a mask all day long; wearing a medical mask for a long time will make the nasal mucosa more fragile, and even more serious will lose the original physiological function of the nasal cavity, affecting its own strength Immunity. At home or in a ventilated place where the population density is not high, masks are not required at all. In addition, in principle, no matter what kind of masks are "aging", need to be replaced regularly. In a strict sense, it is recommended to replace the mask every 2-4 hours. When the mask is contaminated, it should be replaced immediately. However, in real life, the mask itself is a "stressed item", and ordinary people cannot guarantee that they can be replaced in time. As for the N95 protective mask, as long as we can keep it reasonably, it can be used repeatedly. According to the latest US CDC recommendations for the use of N95 masks, if the mask is in short supply, you can consider using the N95 protective mask multiple times, but it is not recommended to use it more than 5 times. Scientifically wear "N95 mask", some details to be done: Although the protective mask can be used repeatedly, pay attention to the wearing details. Wash your hands completely before and after wearing the mask to avoid contaminating the inner and outer surfaces of the mask with viruses, bacteria and other harmful substances; special care should be taken during the second wearing of the mask. Wear a mask to "completely wear" as required, tighten the metal buckle above the nose, and conduct an appropriate air tightness check. It is safe to remove the mask. Do not touch the inner and outer surfaces of the mask. Touch the bag of the mask with one hand to remove the mask. The removed masks should be "stored properly". If at home, it is recommended that they can be placed in a ventilated and dry place to dry, and then placed in a sealed and sealed bag; if the conditions are not available, they can also be placed directly in a clean seal In the bag. Of course, if your protective mask has shown obvious damage and contamination, please replace the mask immediately. Wearing and using masks scientifically, these details need to be clarified and done by everyone; in special times, special treatment.Disposable Protective Face Masks price website:http://www.tiexiongmask.com/face-mask/disposable-protective-face-masks/