Double couplers

Double Couplers at LTT – Your Specialist for Event Technology

Double couplers are the reliable connection whenever You need to join truss and tubes safely on stage or at trade fairs. At LTT You find a comprehensive range of couplers from 50 kg to 750 kg working load, TÜV tested, in silver and black.

Whether You build lighting rigs, exhibition stands or complete stage structures, the right double coupler turns loose tubes into a stable, load-bearing system. As Your specialist for event technology with over 25 years of experience, we supply couplers that meet professional demands.

Browse the range below and discover the ideal solution for every rigging task – with fast dispatch straight from Germany.

What Is a Double Coupler? Fundamentals and Function

A double coupler is a two-part clamp that connects two tubes or truss chords crosswise, holding them firmly together for load-bearing structures. In event technology, the term double coupler (also called swivel coupler or half coupler assembly) describes a rigging fitting used to anchor and fasten truss, pipes and equipment overhead and on the ground.

Each double coupler consists of two coupler halves joined by a bolt. The tube is clamped inside the jaws and secured with an M12 wing nut, spring washer and flat washer. This creates a positive, friction-locked connection rated to a defined working load limit (WLL/SWL).

How a double coupler differs from adjacent products

Unlike a half coupler – which fixes a single tube to a beam or truss chord – a double coupler joins two tubes at once. And unlike a hook clamp, which simply hangs equipment on a bar, a double coupler forms a genuine structural connection between two profiles.

Important for professional event use: double couplers in this range are made from aluminium 6061 T6, not from steel or stainless steel. The many stainless and galvanised steel couplers found in fencing, plumbing or livestock applications are unsuitable for overhead rigging – they lack the declared load ratings and TÜV certification required for suspending loads above people.

Applications and Use: Where Double Couplers Prove Themselves

Double couplers are used wherever tubes and truss need to be connected securely and quickly. Their main task is the load-bearing joining of two profiles in temporary and permanent event structures.

Typical fields of use

• Stage construction: bracing, tying off and connecting truss chords in stage roofs and backdrops.
• Trade fair stands: anchoring signage tubes, banners and lighting bars to a truss frame.
• Lighting rigs: fixing crossbars, side sticks and secondary tubes to the main truss for a clean overhead suspension.
• Ground support: joining vertical and horizontal tubes in tower and portal systems.

For the tubes and truss themselves, take a look at our aluminium truss ranges, and for supplementary clamps browse our wider clamps and hooks assortment. Double couplers are the perfect partner to Naxpro-Truss systems, letting You set impressive structures in scene while keeping every load fully under control.

Types and Variants of Double Couplers

Double couplers come in several models so You can match the fitting exactly to Your rigging task. The two most important variants are defined by their movement and by the tube diameter they accept.

By rotation type

• 360° swivel double coupler: both coupler halves rotate freely around the connecting bolt, so You can join two tubes at any angle.
• 90° fixed double coupler: the halves are locked at a right angle, ideal for clean perpendicular crossings; some models can be fixed at 0° or 90°.

By tube diameter

• 35 mm variant: for 32–35 mm tubes, matching slimmer truss chords.
• 48–51 mm variant: the classic 50 mm coupler for standard event truss.

By width and colour

Double couplers are available in narrow and wide bodies (for example 30 mm coupler width) and in two finishes: natural silver aluminium and black powder coated. The choice of variant depends on angle requirements, tube size and the visual demands of Your production.

Comparison: Half Coupler vs Double Coupler vs Hook Clamp

Choosing the correct coupler type saves time and keeps Your structure safe. The comparison below shows how the three most common clamp types in our clamps and hooks range differ.

In short: use a double coupler when You need to connect two tubes into a load-bearing structure, a half coupler to anchor a single tube, and a hook clamp when You only want to suspend a fixture. All three are stocked in aluminium 6061 T6 with TÜV-tested load ratings.

Technical Buying Criteria: Load Capacity, SWL and Safety Standards

The most important technical criteria for a double coupler are the working load limit, the tube diameter and the certification. Getting these right is essential for safe overhead rigging.

Load capacity and SWL

Our double couplers cover a working load range from 50 kg up to 750 kg SWL, with common models rated at 500 kg. The SWL (safe working load / WLL) is declared per individual item and printed or documented for each coupler. A typical 500 kg / 50 mm swivel coupler weighs approximately 0.832 kg per clamp.

Closure and hardware

Standard closure is an M12 wing nut with spring ring and flat washer, giving repeatable, tool-free clamping with reliable holding force. The two coupler halves are joined by a through bolt.

Certification and standards

Professional double couplers are TÜV tested and their load rating follows the requirements for overhead rigging. In Germany the relevant regulation is DGUV Vorschrift 17 (formerly BGV C1), which governs the safe suspension of loads above persons in the entertainment industry. Always keep the declared SWL as the binding maximum and never exceed it.

Material

Event-grade double couplers are manufactured from aluminium 6061 T6 – a high-strength, lightweight alloy. This is deliberately used instead of steel or stainless steel, which are heavier and, in fencing or plumbing grades, carry no rigging load rating.

Tube Diameters and Naxpro-Truss Compatibility (35, 50 and 60 mm)

Matching the coupler to the exact tube diameter is the key to a secure connection. Double couplers connect tubes roughly in the 35 to 51 mm range, with dedicated variants for smaller and larger sizes.

Mapping couplers to Naxpro-Truss series

Unlike most suppliers, we map our couplers directly to our own Naxpro-Truss tube diameters so You can pick the right clamp instantly:

FD21–24 uses a 35 mm main tube, so it pairs with the 32–35 mm coupler. The popular FD31–44 and heavy-duty HD31–44 series both run on a 50 mm main tube (2 mm and 3 mm walls respectively) and take the standard 48–51 mm double coupler. The heavy GS94 system uses a 60 mm main tube with 5 mm wall and 40 x 3 mm diagonals, so it requires a matching 60 mm fitting. Always measure the outer tube diameter and compare it with the coupler jaw range before ordering.

Buying Guide: How to Choose the Right Double Coupler

Choosing the right double coupler comes down to three questions: which tube diameter, how much load, and swivel or fixed? Work through them in order and You will land on the optimal solution every time.

Step 1 – Determine the tube diameter

Measure the outer diameter of both tubes You want to join. For 35 mm truss chords choose the 32–35 mm variant; for standard 50 mm event truss choose the 48–51 mm coupler; for 60 mm systems select the dedicated 60 mm fitting.

Step 2 – Define the required SWL

Calculate the load acting on the connection and add a safety margin. Then pick a coupler whose declared SWL clearly exceeds that value – our range runs from 50 kg to 750 kg. Never plan a structure at exactly the coupler's rated limit.

Step 3 – Swivel or fixed?

• Need to join tubes at an angle? Choose a 360° swivel double coupler.
• Need a clean perpendicular crossing? A 90° fixed coupler is stiffer and faster to align.

Step 4 – Width and finish

Select a narrow or wide body to suit Your truss geometry and pick silver aluminium or black powder coated to match Your stage look. As a rule of thumb, buy a few spare couplers – on a busy show floor they are quickly needed.

Brands and Manufacturers for Double Couplers

At LTT You find double couplers from established event-technology manufacturers, so You always get certified, high-quality branded products rather than untested hardware-store parts.

Manufacturers in this range

• Naxpro-Truss – our own leading truss brand, with couplers perfectly matched to FD, HD and GS series tube diameters.
• Riggatec – specialist accessories and rigging hardware for event technology.
• Doughty – renowned professional clamps and couplers, including all-weather swivel versions.
• Global Truss and Alutruss – widely used aluminium truss systems with compatible couplers.
• Showtec and Eurolite – reliable stage and lighting hardware.

Because LTT is not only a dealer but also a manufacturer with its own production in Germany, we can advise You precisely on which coupler fits which truss series. That combination of brand choice and in-house expertise is exactly what makes us a dependable partner for professionals.

Accessories for Double Couplers

The right accessories keep Your double couplers working reliably show after show. Around each coupler You will typically need a handful of matching parts and complementary rigging hardware.

Useful accessories and spare parts

• Spare M12 wing nuts, spring rings and flat washers – the wearing parts most often lost or replaced.
• Half couplers and hook clamps – to complete a mixed clamp set for varied rigging tasks.
• Safety steels (secondary suspension) – mandatory backup securing for overhead loads.
• Truss and tubes – the profiles Your couplers connect, available in our truss range.

For the full selection of complementary fittings, browse our clamps and hooks category, where couplers, clamps and hooks are gathered in one place. Stocking a small kit of spare hardware means Your rig is never held up by a single missing wing nut.

Installation, Torque and Inspection Tips for Professionals

Correct installation and regular inspection are what turn a rated coupler into a genuinely safe connection. Follow these professional practices on every job.

Correct installation

1. Check that the coupler jaw range matches the tube diameter before fitting.
2. Push both tubes fully into the coupler halves for the largest possible contact area.
3. Tighten the M12 wing nut firmly by hand until the tube is completely enclosed and held without play. Do not over-tighten with tools beyond the coupler's specification, as excessive force can deform aluminium jaws.
4. Verify the swivel setting (angle for 360° models, right angle for fixed models) before loading.

Inspection and care

• After assembling a structure, check every connection for firm seating and re-check before loading.
• Inspect couplers regularly – at least before each major use – for cracks, deformation, thread damage and wear on the wing nut.
• Never exceed the declared SWL and never use a damaged coupler.
• Withdraw defective couplers from service immediately and replace them.

These steps reflect the duty of care required under DGUV Vorschrift 17 for overhead rigging and help You avoid the most common problems on site.

Material and Finish: Aluminium 6061 T6 in Silver and Black

The material and finish of a double coupler directly affect its strength, weight and appearance. For professional event use the answer is clear: aluminium 6061 T6.

Why aluminium instead of steel or stainless

Aluminium 6061 T6 is a heat-treated, high-strength alloy that combines excellent load capacity with low weight – a typical 50 mm swivel coupler weighs only around 0.832 kg. That keeps Your rig light and fast to handle. Many couplers found in fencing, plumbing or hydraulic ranges are galvanised or stainless steel; while corrosion resistant, those grades are heavier and generally lack the declared, TÜV-tested load ratings required for suspending loads above people. For event rigging, aluminium 6061 T6 is the professional standard.

Finish options

• Silver aluminium: the natural, untreated look – neutral and hard-wearing.
• Black powder coated: a discreet finish that disappears against dark truss and stage backdrops.

Both finishes offer the same load performance, so Your choice is purely about the visual result You want to achieve on stage.

LTT – Your Expert for Event Technology

Whether You are equipping a touring stage, a trade fair stand or a permanent club install, LTT gives You certified double couplers and the expert advice to match them precisely to Your truss. As a manufacturer with our own production in Germany and more than 25 years of experience, we are a dependable partner for technicians, agencies and B2B resellers alike.

Every order ships from Bocholt, Germany, with free delivery from €69, optional express dispatch and the reassurance of our 3-year LTT warranty. To complete Your setup, explore our aluminium truss systems and the wider clamps and hooks range – so You find the optimal solution for every rigging task in one place.

Have a question about the right coupler for Your truss series? Simply get in touch – we are glad to help.

FAQ – Questions & Answers