A gland is a kind of stuffing box and is used to seal a revolving shaft against a fluid. The gland nut allows the packing material to be compacted to form a liquid seal. On oil rigs, for example, the shaft of a hand pump or wind pump is sealed with a gland where the shaft exits the borehole.

Other types of sealed connections that do not have moving parts can also be referred to as glands.

A Compression seal fitting is also known as a sealing gland. It is used to seal certain types of constituents when the constituent must pass through a pressure or border. A compression seal fitting may serve more than one purpose like:

• Restricting the constituent from moving as a result of pressure.
• Preventing the leakage of gas/liquid as used in many industries like the Oil refining, Petroleum, Natural gas and Refining industries. 

A compression seal fitting uses powered components and inertia to compress a spongy sealant inside a body which will create a seal.

A single compression seal fitting may create a seal on single or multiple components. Sealing glands that are intended to seal on a single component may consist of, a body, cap, sealant and a ‘follower’, where as those sealing on multiple components also incorporate a seat and an anti-slip pin to stop wires or conductors from twisting and being severed. One or several insulators could be included when electrical segregation is required.

Single component compression seal fittings are used to seal a single component such as a temperature probe, pipes or related parts. Multiple component compression seal fittings are intended for use with multiple components of the same or differing diameters.

There are several different types of glands which include:

• The Mid-lock glands which is ideally used for sealing metal components or in high vibration surroundings.
• The Electrode gland which fully segregates electrical power where a sealant substance is used for high performance and chemical resistance.
• The Split gland which seals cables when larger connectors are affixed and are intended for sealing components that can go through the gland body, but do not pass through the internal components.