The unique concave fold pattern design ensures 100% effective filtration area and maximum operating efficiency. Strong durability, using advanced foreign technology to prepare specialized filter cartridge adhesive for bonding. The optimal fold spacing ensures uniform filtration across the entire filtration area, reduces filter element pressure difference, stabilizes airflow in the spray room, and facilitates cleaning of the powder room. The folding top has a curved transition, which increases the effective filtration area, maximizes filtration efficiency, and prolongs service life. Rich in elasticity, low hardness, single ring sealing ring.