Class is in session. Classic 3-ring binder paper is printed inside with the French conjugation of. To buy. (I buy, you buy, he, she buys, etc) The Mighty Wallet is tear-resistant, water-resistant, expandable & recyclable. Made from Tyvek (think express mail envelopes), these cool wallets resist tearing because of thousands of interlocking plastic fibers spun in random patterns, giving them incredible strength. The ingenious origami construction was & is the original folded Tyvek wallet designed by Terrence Kelleman. The stitch less design reinforces the materials own strength & allows these very slim wallets to instantly expand & adapt to your own personal storage needs. The Mighty Wallet will expand right before your eyes (watch the videos) Because of the slim, lightweight & water resistant features, you can take these cool wallets anywhere. They make great night out wallets for a slender silhouette & the writable surface conveniently acts as a quick note pad on the go. In time, the Mighty Wallet will gradually soften & patina but, even after years of wear, it will still offer surprise & solicit intrigue. Dim: