Descriptions. Specifications: 13mm 0.22um, 13mm 0.45um, 25mm 0.22um, 25mm 0.45um Material: Hydrophilic PTFE. Needle filter applied to a small sample of laboratory filtration, adsorption of its small sample, thus ensuring the maximum recovery amount or a small amount of high-value samples, the filter housing is made of polypropylene material, ultrasonic welding, adhesive-free agents, and thus