The Ideal Stock System, manufactured to Bo Hagner’s original specification, the original system uses 7 holes (fits either 3 or 4 ring binders). The polyester pockets block ultra violet light which stops fading and repels moisture. Each pocket is bonded to the card with an adhesive rubber strip. This strip flexes and retracts to hold the stamps firmly. Every part of the Hanger sheet is chemically inactive which means no danger to your stamps, no matter how long they remain in a Hagner sheet. Available a single and double sided sheets. All leaves are punched 7 Ring, supplied in packs of 10. Overall Leaf Size of 189 x 254mm.