The flexi-spine booklet has the following key features:
1. A thin spine that allows for storage in a slab or acrylic case (e.g., one touch mag holder),
2. Built in one single piece, so both strength and flexibility are enhanced,
3. Spine flexes in from -180 to +180 degrees and can twist,
4. Leaves can be added in custom configurations,
5. Multiple leaves means you can include your business card and/or COA with your custom, for a comprehensive collectible, and
6. Deep cavities mean you can embed thick and/or heavy objects

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