A come-along is a hand operated ratchet lever winch. A winch is a mechanical device used to wind a rope or cable, while a ratchet is a mechanical brake that keeps the line from unwinding. A come-along is convenient and portable enough to use in almost any situation, because it is small enough to carry in one hand and weighs an average of only ten pounds (about 4.54 kilograms).

A come-along is used for pulling joints together, for straightening heavy panels while putting them in place, as a safety tie, and for pulling the frame of a new construction together during its raising. A come-along can also be used for stretching, lifting, and lowering objects. In addition to construction and industrial applications, a come-along is useful for towing boats, cars, and gliders. On boats and ships, it can be used to pull anchor or mooring lines, sheets, and halyards.

A come-along can be purchased in a variety of sizes and weight lifting capacities for varying construction needs. Lifting capacity generally ranges from one to three tons (907.19 to 2721.6 kilograms), with a six to twelve foot (about 1.83 to 3.66 meters) lift height. It is important to adhere to the recommended weight limits provided with a come-along, as the device is susceptible to fatigue fractures if repeatedly operated at even a small percentage of its tensile breaking strength.

Often, a come-along is designed with internal clutches in order to limit operating loads. Within these limits, however, the wire rope can rust from the inside out. In addition, the cross sections of chain links are reduced through wear. Frequent lubrication will extend the life of the come-along.

A come-along can also be equipped with a web strap to prevent twisting, as well as a safety feature called a breakable stress link. If the come-along is overloaded, the stress link breaks. This lets the operator know to back off the load before the fiberglass handle snaps, preventing both personal injury and equipment damage. The stress link can be easily replaced if damaged. Replacing the stress link of the come-along is far less costly and difficult than if further damage were to occur to the equipment due to excessive stress.