A physical object intended to prevent something to pass.

An attenuator is a telecommunication device that reduces the amplitude of a signal without appreciably distorting its waveform. Attenuators are usually passive devices. The degree of attenuation may be fixed, continuously adjustable, or incrementally adjustable.

A self-controlled device for making, carrying, and automatically interrupting and reclosing an alternating-current circuit.

An automatic tracking system used on ships and by vessel traffic services (VTS) for identifying and locating vessels.

A physical object that is automatic and designed to initiate the operation of circuit-breakers and/or disconnectors in a substation according to a specific programme.

A dynamic compressor in which the gas is accelerated by the action of a bladed rotor and where the main flow is along the rotation axis of the rotor.

A detecting element that is intended to detect axial displacement.

A transmitter measuring an axial displacement and generating a standardized output signal representing the axial measured displacement.

Is a gas flow damper intended to adjust an air flow rate through a duct.

A ball valve that is equipped with an actuator that manipulates a stream of fluid in the response to a signal from an external sensing element and with input of energy from an external source.

A rotary valve that has a ball closure member.

A railing or wall to provide a protective edge to prevent people from falling over the edge of stairs, a roof or mezzanine work area.

A large flat-bottomed boat that is built for carrying goods and people on rivers and canals or in harbours, with or without sails, towed by a tug or horse. Also a similar boat with its own engine.

A container intended to store liquid or solid material partly or totally below grade and that is typically open.

A container that has a characteristic shape and that is made of material with an open structure.

A direct current power supply unit intended to supply stabilised DC electric power according to specified levels and tolerances.

A direct current power supply unit for charging batteries.

A compartment or area within a building with a specified function.

A support that is a large and straight piece of normally timber or iron forming one of the main structural member of a building or supporting structure.

An equipment item that can be clamped to a beam to provide an attachment.

A pump jack that converts rotary motion to vertical reciprocating motion.

A physical object intended to support and locate a moving or static element and capable of reducing friction and transfer forces in a connection.

A physical object that is a hollow body with a flared mouth made of cast metal. Formed to emit a clear musical sound by the sonorous vibration of its entire circumference when struck by a clapper, hammer or other appliance.

A conveyor that consists of a suitably tensioned endless belt made from hard wearing materials and arranged to run over rollers.

A two or three wheeled vehicle designed to be propelled solely by human power, or a two or three wheeled vehicle that is a power assisted pedal cycle.