[citation needed] In 1989, the LEGO pneumatic line was revamped, and a new cylinder and pump piece were introduced.

The chief difference is that the new cylinder had two input valves now, which allowed both pushing and pulling without needing complex circuits involving the distribution block piece.

The small pump did not have a spring on it, and it was designed to be operated by a motor, which would allow for continuously running pneumatic creations.

The small pump only appeared in two sets — 8868 Air Tech Claw Rig (1992) and 8049 Tractor with Log Loader (2010) — and a few service packs.

This piece is very popular with the enthusiast community, but many feel that it was underutilised by LEGO, as it only appeared in 3 model sets and a parts pack.

In 2003, LEGO discontinued the old cylinder and switch parts, and made new "studless" versions to fit in with their transition towards removing studs from Technic sets.

It also has a larger contact pad at the top of the pump and contains a relief valve to limit the maximum pressure in the system.

The Generation 2 cylinders have 2 inputs (and come in studded, studless, and small versions), and work on pressure in both directions.

Tubing can connect to a switch, air tank, T-junction, cylinder, pump, distribution block, or flex-hose.

Flex-hoses aren't actually considered pneumatic pieces; they were designed as part of the Technic system for a different purpose, but Lego fans have discovered that pneumatic tubing actually fits over flex hoses pretty well, so many people use them as tubing extenders whenever they are needed.

Lego pneumatic came in an uncut form in earlier sets, and were required to be cut into smaller pieces using scissors.

In newer sets, such as the 8049 technic tractor and log loader, the 8110 Unimog U400, the 42053 Volvo EW160E Digger and the 42043 Mercedes Benz Arocs 3245, the tubes are already cut to size.

The pneumatic elements are most commonly used to resemble and take the function of hydraulic cylinders in appropriate models, actuating a digging arm or crane, for example.

Because a slight delay is involved between increased pressure and cylinder movement, various feedback loops can be used whereby one pneumatic component can activate another in a series of mechanical events.

The Fischertechnik system includes an electrically activated air solenoid, a feature not available in the Lego range.