Original two-piece, self-locking fasteners give you a secure, book-like binding to help you save on document storage space. Sturdy fasteners in specialty sizes are great for non-standard applications. Made from heavy-gauge, high-grade material for added durability. Compressor. Fastener Subtype: Two-Prong Compressor; Center To Center: 2.75"; Material(s): Metal; Color(s): Silver.