Couplers are the fittings that hold the tubes of scaffolding together

Couplers are the fittings that hold the tubes of scaffolding together. They're often called scaffold couplers and one will find three different kinds: right-angle couplers, putlog couplers and swivel couplers. Other common materials being used include base plates, ladders, ropes, anchor ties, reveal ties, gin wheels and sheeting.

The key elements of scaffolding are called standard, ledgers and transoms. The standards, often known as uprights, are the vertical tubes: extended from the ground up. They are used to transfer the entire weight of the structure to the ground where they rest on something called a base plate that spreads the load. The base plate has a shaft in its centre to support the tube.
Ledgers are horizontal pipes that connect between standards, Transoms rest upon the ledgers at right angles. Main transoms are placed next to the standards; they hold the standards in position and provide support for planks. Intermediate transoms, as indicated by its name, are the ones placed between the main transoms to provide added support for planks.
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