No need for expensive crimping tools—these fittings make air conditioning and refrigeration assemblies with clamps. Instead of a crimper, they use two clamps that you tighten against a cage on your fitting with pliers. Both fitting ends swivel until tightened, so you don't have to rotate the entire hose during installation. The cage and clamps stretch out after use, so they shouldn't be used again.

Straight adapter kits include everything you need to connect one end to aluminum tubing. Braze the fitting to your tube with one of the braze rings. To prevent leaks, slip an O-ring on after the brazed joint cools. To connect these fittings to a hose, you’ll need a cage, clamps, and hose clamp pliers.

Fittings with an O-ring pilot create a leak-tight seal, so they’re often used in commercial and vehicle air conditioning systems. When you screw the fitting onto your tube, the bead and the pilot squeeze the O-ring, which fills in any gaps. The pilot also helps guide your hose onto the fitting, making it easy to properly align and secure the connection.

Fittings with a 45° flared end are also known as SAE fittings.

Commonly used in high-pressure welding applications, these nipples connect your tank to the inlet of a pressure regulator. One side has a threaded pipe end and the other side is designed to sit inside a threaded nut (sold separately) so you can make a threaded connection.

Brass nipples have good corrosion resistance and are softer than 316 stainless steel nipples, so they're easier to thread together. Chrome-plated brass nipples have better corrosion and wear resistance than unplated brass nipples and have a bright, shiny appearance.

Nipples that tighten by hand should be paired with a nut with a plastic grip.

Slide a high-pressure hose nipple for compressed gas into one of these nuts to connect a pipe to the inlet of a pressure regulator. They are also known as CGA (Compressed Gas Association) nuts and inlet nuts.

Brass nuts have good corrosion resistance and are softer than 316 stainless steel nuts, so they're easier to thread together.

Note: Nuts have a CGA, BS, or DIN number that corresponds to a specific type of gas. Choose a nut with the same number as your tank and other system components.

Often used in heating and cooling systems, this tubing insulates refrigerant to efficiently transfer heat between components. It's frequently referred to as refrigeration and air conditioning tubing. This tubing consists of a copper tube insulated in rubber. The copper tubing resists corrosion and has excellent heat transfer qualities. The outer insulation has a closed-cell design, so it prevents moisture from seeping through and corroding the copper tubing. This tubing is generally rigid because of the copper tubing inside and is stronger than plastic and rubber tubing. Use it in medium- to high-pressure applications.