Beistle issued three “domino hat mask” designs between 1926 and 1931. Most of the time they were just stand-alone masks as shown on pages 236-237, but occasionally they were stapled to a random band hat, as in this listing. The entire bottom section of the mask is missing, so this is more of a substantial remnant than anything else. Virtually all of its collectible value has been eliminated due to its poor condition.
11/13 Update: …And yet this sold, in these bubbly times, for $86!