Abstract: A slide compression mechanism for a flexible post binder is disclosed which includes specially constructed means for limiting outward movement of each compressor member relative to the channel member on which it is slidably mounted. More particularly, this motion limiting means comprises at least one pair of specially constructed interengageable longitudinally aligned stops positioned internally of the channel member. The slide compression mechanism also possesses a hook portion having a raised lip on the hook end which not only facilitates automatic assembly of the slide compression mechanism onto the channel member but also serves as a means for limiting the inward movement of each compressor member relative to the channel member.