Correct Johnbrown, I believe I did make an error stating they were 6 mil thick, and are probably 3 mil thick? Bes at MusicDirect can probably confirm this.
What I think the material is, is Mylar, and heck, I got Snare Drum, Snare Side Heads that are made of 3 mil thick Mylar! The Remo Ambassador Snare Side is a 3 mil thick Head.
It is not a "stretchy" material, thus when you go to open the flap to extract an LP, it doesn't stretch all out of shape like a poly outer sleeve will. Not to say that they are bulletproof, but with care will last many years, and will protect your vinyl investment.
As you said John, they are crystal clear, and I'm very happy somebody came along making a quality product like this. Mark
What I think the material is, is Mylar, and heck, I got Snare Drum, Snare Side Heads that are made of 3 mil thick Mylar! The Remo Ambassador Snare Side is a 3 mil thick Head.
It is not a "stretchy" material, thus when you go to open the flap to extract an LP, it doesn't stretch all out of shape like a poly outer sleeve will. Not to say that they are bulletproof, but with care will last many years, and will protect your vinyl investment.
As you said John, they are crystal clear, and I'm very happy somebody came along making a quality product like this. Mark