Vintage Hawaiian Trucker Hat Rope Flat Brim Green Orange Parrot Nissin Cap

Super rad vintage Hawaiian print cap with flat brim, orange rope, and fun lightweight nylon fabric printed with a tropical design of green and orange with a blue parrot on the right side. It has a size adjuster on the back I have not seen before, so I don't know how to work it, looks like you can make it smaller. Great hat! Very good vintage condition with nice bright colors, some yellowing on front of inside band (see photos please)