TOPS Cardinal XtraLife Locking Round Ring Reference Binder, 8.5 x 11 Inch Sheet Size, 2 Inch Capacity, Blue (25802CB) Strong, XtraLife polyolefin material will not stick to prints, photos or photocopies to produce and dispose of than standard vinyl Seams and hinges are guaranteed for one year against cracking Cold-crack safe to -50 degrees Fahrenheit SureLock rings lock to prevent accidental opening For letter size documents