A choice of blonde,grey,black or brown netting set over all or part of the wig for opera, dancers,performers  who need more security on their wigs.  This must be discussed how and if this Is advisable for each wig.  This comes with a few attach points and is not meant to be removed. This is excellent on buns. Not advised for loose waves or hanging curls ( it is a possible encumbrance).  This is for each wig.  So it needs to be discussed and noted per wig.