These are Kodak gelatin filters in borosilicate B-glass. (The 18a is actually solid Woods glass). Most are in excellent condition and noted if otherwise. 2x2 50mm, 3x3" 75mm, and 4x4" 100mm sizes. All are ready for action.  Same day shipping if ordered before 10am eastern time (US). Check out my other Wratten filters in my store. Frames and holders not included but...

My Ebay store is a grand Wratten Filter PARTY! Check out my other listings.

Also see filter frame holders at https://www.ebay.com/itm/New-Kodak-Wratten-Gel-Filter-Holder-for-3x3-inch-75mm-filters-67mm-connection/112280537155? I also have 2x2 and 4x4 filter frame holders available.