Includes one lock and one upper hasp. Numbers read correctly to viewer with button on left side. Could be installed as a right hand lock but numbers would be "upside down". Great for use on briefcase or musical instrument case repairs. The red tab can be removed and the combination lock set to any numbers desired. The square portion is approximately 2.5 by 1.25 inches. It is 1/4 inch deep. The lock mechanism sticks out beyond that in back, so must be recessed into your case. See more installation instructions below. This lock is called a LH lock...."left hand" lock, since the flip tab is on the left side. Great for many applications...medical cases, gun case, musical instrument, brief case, etc. High quality locking device and excellent finish plating. Fasteners not included. The lock in various situations can be installed with wood screws, luggage rivets, or pop rivets too (not included). Different materials require different types of rivets, for example plastic versus wood. Installation note: The face of this lock is a raised type - see pics. The tumbler mechanism sticks out in back, so there has to be a recessed area for it to fit in. Most brief cases will accommodate that by having a hole in place. On some cases you may have to make a small square hole for the lock part to rest in. This lock has a body that is raised 1/4 inch and therefore requires a case that has a raised valance for the hasp. Instructions are included on setting the combination.