Camlock Fittings Explained: Types A, B, C, D, E, F, DC and DP

Camlock fittings—also called cam and groove couplings—are one of the fastest and simplest ways to connect and disconnect hoses, pumps, tanks, and piping. They’re used throughout water trucks, construction equipment, agriculture, industrial fluid transfer, and many other applications where a threaded connection would be too slow or inconvenient.

The system is straightforward, but selecting the correct camlock can be confusing because the letters A, B, C, D, E, F, DC, and DP describe specific combinations of camlock, pipe thread, and hose connections.

This guide explains what each camlock type is and how to choose the right fitting for your application.

How Does a Camlock Fitting Work?

A camlock connection consists of two mating parts:

• A male adapter, sometimes called the male cam or adapter end
• A female coupler, which contains two cam arms

The male adapter slides into the female coupler. When the two cam arms are pulled down, the cams engage the groove around the male adapter and draw the two fittings together.

A gasket inside the female coupler provides the seal.

This design allows a hose or pipe connection to be made in seconds without threading fittings together or using tools.

On water trucks, camlocks are commonly used between:

• Water pumps and suction hoses
• Tank outlets and plumbing
• Fill hoses
• Discharge hoses
• Spray system plumbing
• Hydrant or pond-fill equipment
• Portable transfer pumps

Understanding Camlock Types

The letter assigned to a camlock tells you which connection is on each end of the fitting.

Type A — Male Adapter × Female Pipe Thread

A Type A camlock has:

Male cam adapter on one end
Female pipe thread on the other

Type A fittings are commonly threaded onto equipment with male pipe threads while leaving a male cam connection available for quick hose attachment.

Typical applications include pump ports, tank plumbing and threaded pipe assemblies.

Type B — Female Coupler × Male Pipe Thread

A Type B camlock has:

Female cam coupler with cam arms
Male pipe thread on the opposite end

Type B fittings are useful when equipment has a female threaded port and you want to convert that connection into a female camlock.

The cam arms are located around the female cam connection—not around the threaded portion of the fitting.

Type C — Female Coupler × Hose Shank

A Type C camlock combines:

Female cam coupler with cam arms
Hose shank on the other end

This is one of the most common fittings found on transfer hoses.

The hose slides over the shank and is secured using an appropriate hose clamp, band clamp, crimp sleeve, or other retention system suitable for the hose and operating pressure.

Type C fittings are especially common on water truck suction and discharge hoses.

Type D — Female Coupler × Female Pipe Thread

A Type D camlock has:

Female cam coupler with cam arms
Female pipe thread on the opposite end

These are frequently used on equipment or plumbing that already has a male threaded connection.

A Type D can be threaded onto the equipment and provides a female cam connection for rapidly connecting and disconnecting a hose.

Type E — Male Adapter × Hose Shank

A Type E camlock has:

Male cam adapter
Hose shank

Like the Type C, it is commonly installed directly into a flexible hose.

The difference is the camlock end:

• Type C = female coupler
• Type E = male adapter

A Type C hose and a Type E hose can therefore connect directly to one another when they are the same compatible size.

Type F — Male Adapter × Male Pipe Thread

A Type F camlock combines:

Male cam adapter
Male pipe thread

Type F fittings are commonly threaded into female pump ports, valves, tanks and piping systems to provide a male cam connection.

One easy way to remember the difference between A and F is:

Type A = female thread
Type F = male thread

Both have a male cam adapter on the opposite end.

Type DC — Dust Cap

A Type DC is a camlock dust cap.

It uses the same cam-arm mechanism as a female coupler and locks over a male cam adapter.

Dust caps are useful for protecting open plumbing from:

• Dirt
• Gravel
• Insects
• Debris
• Contamination during transport

They can also help contain residual fluid remaining inside a hose or fitting, although a dust cap should not automatically be treated as a pressure-rated shutoff device unless the manufacturer specifically rates it for that purpose.

Type DP — Dust Plug

A Type DP is a dust plug designed to fit inside a female cam coupler.

Unlike a dust cap, a DP does not have cam arms. The cam arms on the mating female coupler lock around the groove of the dust plug.

A simple way to remember the two:

DC = cap that fits over a male adapter
DP = plug that fits into a female coupler

Camlock Type Quick Reference

Choosing the Correct Camlock Size

Camlock fittings are typically identified by their nominal connection size, such as:

1½", 2", 3", 4" and larger sizes

It is important not to simply measure the outside diameter of a fitting and assume that measurement is the nominal camlock size. Pipe and hose sizes are nominal sizes, and the actual measured dimensions will be different.

For replacement parts, identify:

1. The camlock size
2. Whether you need a male adapter or female coupler
3. The connection required on the opposite end
4. Thread type and size
5. Fitting material
6. Gasket material

Brass, Aluminum and Stainless Camlocks

Camlock fittings are available in several materials.

Brass

Brass camlocks are durable, corrosion resistant and well suited to many water-transfer applications. Their weight and substantial construction also make them popular for equipment that sees frequent connection and disconnection.

Aluminum

Aluminum fittings are considerably lighter and are extremely common on water trucks, agricultural equipment and general water-transfer systems.

Stainless Steel

Stainless camlocks provide excellent corrosion and chemical resistance and are commonly selected for demanding industrial applications.

The proper material depends on the fluid being transferred, environment, operating pressure and equipment requirements.

Don't Forget the Camlock Gasket

The gasket inside the female coupler is what actually creates the seal between the fittings.

If a camlock begins leaking, the fitting itself may not be the problem.

Check for:

• Missing gasket
• Hardened gasket
• Cracked or damaged gasket
• Incorrect gasket thickness
• Debris on the sealing surface
• Damaged male adapter sealing surface
• Worn cam arms or pins

Gasket material should also be compatible with the fluid being transferred.

A Common Camlock Selection Mistake

One of the easiest mistakes is ordering the correct thread but the wrong cam connection.

For example, both Type A and Type D can have female pipe threads.

But they are completely different on the camlock side:

Type A → male cam adapter

Type D → female cam coupler with cam arms

Likewise:

Type F → male cam × male thread

Type B → female cam × male thread

Looking at both ends of the fitting before ordering prevents most camlock selection mistakes.

Camlocks on Water Trucks

Water truck plumbing is particularly well suited to cam and groove fittings because hoses are frequently removed, changed or rerouted.

A typical system might use a male adapter on the pump or tank and female-coupler hoses that can quickly be moved between connections.

Keeping a few common adapters, dust caps and plugs on the truck can also make field repairs considerably easier when equipment configurations change.

Need Help Identifying a Camlock?

If you aren't sure which camlock fitting you have, identifying it usually only requires three pieces of information:

Camlock size + cam connection type + opposite connection

For example:

3" Type D = 3" female cam coupler × 3" female pipe thread

or

2" Type E = 2" male cam adapter × 2" hose shank

IronRidge Truck Parts supplies cam and groove fittings and other water truck plumbing components for repair, replacement and new installations.