Clasp
— Magnet. Clasp based on the action of a strong permanent magnet. When it is closed, the magnet “sticks” to a special metal element on the other half of the cover, or, in the case of flips (see “Type”), to the body of the tablet. The main advantages of such a fastener are simplicity of design and durability: the magnet practically does not wear out, does not lose efficiency over time, and does not suffer from frequent opening/closing. As a disadvantage, one can name a relatively weak fixation; however, magnetic fasteners are usually designed to minimize this disadvantage and are reliable enough for most applications. Thanks to this, the magnet is one of the most popular types of fasteners. At the same time, we note that when using covers with such clasps, you need to exercise some caution: they should not be placed next to credit or other magnetic cards, because a magnet may render such a card unusable.
— Hook-and-loop. The Hook-and-loop fastener consists of two surfaces: on one there is a layer of felt, on the other — microscopic hooks that catch on the felt fibers when the surfaces come into contact. This provides a fairly strong grip. The disadvantage of Hook-and-loop is increased wear with frequent use, because. with each opening, part of the fibers breaks out with hooks. Therefore, such fasteners are rather poorly distributed; they are mainly used in bags (see "Type"), where opening and closing the clasp is relatively infrequent.
— Elastic. Elasti...c fastening that holds the two halves of the case together. Due to its design features, it is used exclusively in covers (see "Type"), but among this type of covers it is only slightly less common than a magnet (see above). The fact is that the rubber band combines simplicity and reliability of holding, while it does not pose a danger to magnetic cards. Among the shortcomings, one can name a tendency to stretch with inaccurate use (due to which efficiency is lost), and in general, somewhat less durability than a magnet.
— Rivet. Another popular name is "button". By design, such a clasp is similar to a regular button used in clothes: on one half of it there is a curly protrusion, on the other — a recess with a special lock. When closed, the protrusion fits into the recess and locks into place, ensuring a secure fit. Actually, the reliability of retention is the main advantage of rivets. On the other hand, they may require considerable force to open and close. This, firstly, is not very convenient, and secondly, it wears out the material around the button a lot — up to loosening and falling out of the fastener with a relatively intact case. This puts forward separate requirements for the strength of the case itself. Because of all this, rivet fasteners are quite rare.
— Lightning. The zipper is used exclusively in bags (see "Type"), and more often than any other type of fastener. This is the best option given the main purpose of bags: zippers close and open easily and quickly, are quite durable and even provide some degree of additional protection at the ends.
— No zipper. Fasteners, by definition, do not have protective covers (see "Type"); also, models without fasteners are often found in bags that leave one end of the device open and are designed for the fastest access to a tablet or e-book. In other types, this option is quite rare. Also in this category are bags with a drawstring that tightens the inlet neck.
