The metal connectors for the USB and Micro USB ports are solid metal and should function admirably with most cases.
Before using, check that the packaging is intact and confirm the marked expiration date on the outer package and use the mask within the expiration date. Open the mask fully, position the mask with the metal nose strip up. Use both hands to press the metal nose strip to fit the bridge of the nose and achieve a better protection effect. Store the mask in a dry, ventilated, non-corrosive gas environment and away from fire sources and flammable materials.
In summary, they are basically all the same.
They stop 95% of particles >0.3 microns in size. The N95 is the USA Code, KN95 is China code, KF94 is Korea code and FFP2 is the EU code, this includes the UK. KN95, KF95 and FFP2 face masks are N95 face mask alternatives & N95 equivalents. They are all the same.
Cleaning of reusable equipment before sterilisation is recommended but there are no data available on the effective and non-damaging cleaning methods for single-use equipment such as masks.
In general, N95 respirators are designed for single-use prior to disposal.
They masks have 3 ply
Anyone who plans to wear an N95 mask would usually need to shave their beards to ensure a good fit and allow for proper filtration.
These face masks are generally for single use only. See the link below for guidance on when to use masks to avoid wasting them. There have been some recent studies on cleaning masks however, this is not recommended as of yet.
This is the price for a single individually wrapped mask
I have sent you the CE certification separately