Nice enough domain but I don't see huge value.
Here is some *mask* related US sales data if that helps:
masks.info 2009-05-01 $230 Moniker
maskscostumes.com 2008-01-01 $43
hepamasks.com 2006-03-01 $554 Afternic
surgicalmasks.net 2009-12-23 $369 Sedo
facemasks.com 2011-08-15 $5,332 Sedo
Admin