Nose mask size: (WxD) 9.5x17.5 cm. Maximum output width: 15.5 cm. Elastic length: 18 cm. -Made from PPSB masks. - Protein free strap Helping the wearer not lose - Dust filter can prevent dust as small as 0.3 microns - Can be used with fine dust, germs, viruses - Filter efficiency 99.97% [FFP3]