Nylon, meltblown with EAPI filter technology Imported 6-Layer Full Protection: BASE CAMP M Plus face mask is the third generation of BASE CAMP dust mask. Adopted EAPI filter technology and advanced nanotechnology, the filters are upgraded to be 6 layers, which can maximally block exhaust gas, pollen, dust, particles and smoke, etc. Provide reliable protection for daily use. More Breathable & Comfortable: High-quality mesh materials, the reusable face mask is 11.3% more breathable, strengthens air circulation capacity, dissipates heat, also reduces moisture inside to ensure smooth breathing with our breathable face mask. Meanwhile, its elasticity is 6.1% higher for more comfortable wearing. Adjustable for Optimal Fit: Designed with an adjustable hook and loop strap, the adjustable face mask can be adjusted to fit most people for a perfect fit. The closed AEB system helps keep the mesh mask without slipping off your head/face while relieving pressure or pain in the nose and ears. Tips: