I bought 2 split density filters new from B&H and a deep red from Adorama (I think) for a trip that did not happen so I put them away in my camera bag and forgot about them for a couple years. When I stumbled on them and decided to use the Split density filters I got weird wavy lines in the transparency. I assumed it was me. When I next used them I held them up to my eye to judge the scene and guess what, there were the lines. Like looking through water. I checked the red and there they were but worse. Neither store would take them back so I tossed them.