This pen case is finished by lightly moistening the leather and kneading it by hand, giving it a broken-in softness and a relaxed, lived-in look. While the overall silhouette is flat and minimal, the softly padded gussets on both ends offer more strage than meets the eye. The zigzag stitching on the gussets adds a subtle yet eye-catching design detail. About the Leather OIL LEATHER This is cowhide that has been thoroughly tanned using vegetable tannins, then infused with oil and kneaded to enhance its suppleness and durability. It features a moderately oiled, soft, and moist texture. Over time, it develops a rich luster through natural aging. The surface finish is simple, so natural marks and imperfections in the leather are not hidden, but the more you use it, the more character it gainsshowcasing the true appeal of genuine leather.