The mask is based on a Xenomorph Warrior from Aliens and features the distinctive ridged head of the caste. The mask's mouth is open, exposing the inner jaw which also has its mouth open. The mouth is oozing a transparent green liquid, possibly meant to be saliva or the Xenomorph's acid blood.
The original factory tag/label is known to be very hard to find since most tags were taken off after purchasing or used for costume. The tag has "TM ( C within the circle) 1986 , 1991 Twentieth Century Fox" on it. The movie was produced in 1986 and Distortions Unlimited had to get the copyrights to produce the mask in 1991. Thus listed on the tag as 1986 for the movie and in 1991 production of the mask. It takes a lot of time for companies to get the copyrights for production and has to clear Twentieth Century Fox company legal department as well as back and forth to the design department to be as close to the movie representation.