GBC Binding Spines/Spirals/Coils, 3/4" Diameter, 150 Sheet Capacity, CombBind, Black, 100 Pack (4000104) CONVENIENT COMBBIND  CombBind spines allow pages to lie flat for easy reading. Spines won't scratch, chip, peel or discolor over time. Sturdy spines are excellent for busy corporate offices. 19-HOLE PLASTIC SPINES  CombBind spines have 19 holes to provide a secure binding. These strong spines are the workhorse of the binding world. 150-SHEET CAPACITY  Shiny, black spines provide plenty of space to house your printed projects, comfortably securing 150 pages per spine. 3/4" diameter spine size. EASY TO USE  Convenient, multi-purpose spines are designed for use with all CombBind Machines (sold separately). Sleek spines look great with GBC ClearView and Regency covers. 100 PER BOX  A box of 100 spines ensures long-term productivity for all of your binding projects.