Numbered limited edition of 800, 400 of which had a sticker and some also had inserts.
No more than a handful of mispressings exist where the white vinyl disc is Mint Green instead.
It's claimed there may be as few as three copies like this and it certainly reached a good price at auction!
Just noticed my copy of this is numbered a deliciously low 000019, so thought I ought to have a quick crow to the world about it. Image uploaded. Have a look. It's there at the end. That's my one, that is.
I'd assume the "HB" means it was a Huggy Bear promo copy.