Mid Clamps and End Clamps

Let's be honest—when people talk about PV mounting systems, all the attention goes to the rails, the posts, the foundations. But the parts that actually hold solar panels in place are the clamps—mid clamps and end clamps. At Xiamen Honor Energy, we have been in this business long enough to know one thing: if your clamps fail, your entire array is in trouble.

What exactly are mid clamps and end clamps, and why do you need both?

Honestly, they both do the same core job: holding solar panels down onto the rails. But where they sit makes all the difference. Mid clamps go in between two panels.

Picture this—you've got one panel on the left and one on the right, and a mid clamp sits right in the gap, gripping the edge of both at the same time. It keeps the spacing even, stops the panels from drifting out of alignment, and locks everything tight to the rail underneath. Every panel needs two of these—one on each side. End clamps are the bookends. They go at the very start and the very end of each row, grabbing only the outer edge of the first and last panel. Their job is to keep the whole row from sliding sideways when the wind hits. Without them, that row of panels would slowly work its way loose over time. So in plain terms: mid clamps connect, and end clamps cap. Use both, or your array won't stay together for long. End clamps (also called side clamps or edge clamps) are installed at the outer edges of each row of panels. Each end clamp holds only one module's outer edge, acting as a "cap" to prevent the entire row from shifting sideways under strong winds or vibration. End clamps require more careful design than mid clamps because they only grip one panel—under load, they tend to rotate or slip off the frame if not properly engineered. In simple terms: mid clamps handle the connections between panels, and end clamps handle the edges. You need both to turn a row of individual panels into a single, solid structure.

Specifications

Compatible with Most Panels on the Market Our mid clamps and end clamps are designed for maximum compatibility. Mainstream PV modules have frame thicknesses ranging from 30mm to 50mm, and our products cover virtually all of them. Standard mid clamp sizes (module thickness): 30mm / 33mm / 35mm / 38mm / 40mm / 45mm / 50mm Standard end clamp sizes (module frame height): 35mm / 40mm / 45mm / 50mm Clamp length: Standard 40mm, 50mm, 60mm – custom lengths available upon request. Panel spacing (mid clamp): 20mm, 26mm, 28mm, etc.. We also offer adjustable mid clamps and adjustable end clamps that cover either 30/34/38/42mm or 35/40/45/50mm in a single model. Fewer SKUs in your warehouse, less headache on the job site.

Materials and Finish

Aluminium Body, Stainless Steel Hardware Clamps sit outdoors, exposed to sun, rain, and temperature swings year after year. If the material isn't right, they'll rust through in three to five years. Our mid clamps and end clamps are made from aluminium alloy 6063-T5 – the most proven and widely used aluminium grade in the PV mounting industry. It offers high tensile strength, low weight, and excellent corrosion resistance, with a service life of 20-25 years in outdoor environments. Surface treatment is anodised – natural silver or clear finish, with an oxide film thickness of 8-10 microns. This thin film dramatically improves corrosion resistance. Black anodised or electrophoretic coating is also available for special requirements. Hardware is stainless steel 304 or 316 – bolts and nuts that won't rust out while the aluminium parts are still in good shape. Anti-slip pads are made of EPDM rubber (ethylene propylene diene monomer), placed between the clamp and the module frame. These pads serve two purposes: they increase friction to prevent panel movement under wind loads, and they cushion the clamping force to avoid scratching or deforming the aluminium frame. EPDM rubber is UV-resistant and age-resistant, performing reliably from -40°C to 80°C.

What Kinds Do We Offer?

You'd think mid clamps and end clamps are pretty straightforward – and they are, mostly. But over the years, we have learnt that one size definitely does not fit all. Different projects, different panels, different site conditions – they all ask for something a little bit different. So here is what we keep in stock: Standard mid clamps – these are your workhorses. They fit conventional framed crystalline silicon panels, the kind you see on 90% of projects out there. Compatible with module thicknesses from 30mm right up to 50mm. Nothing fancy, just solid and reliable. Standard end clamps – same idea, but for the outer edges. Same thickness range, same straightforward installation. They do exactly what they are supposed to do and they do it well.

Adjustable mid clamps

This is where things get clever. One single clamp covers multiple thicknesses—either 30/34/38/42 mm or 35/40/45/50mm in one model. No more guessing which thickness you need, no more stocking four different parts for four different jobs. Grab one box and you are covered for most scenarios. Adjustable end clamps—same adjustable concept, but for edge positions. Gives you the same flexibility on the ends of your rows. Thin film mid and end clamps—these are a bit of a specialty. Thin film modules are much thinner than standard crystalline panels—we are talking 5 to 7.7 mm. Regular clamps just won't grip them properly. So we make dedicated ones with a narrower jaw profile, designed specifically to hold thin film panels securely without damaging the edges. That is our line-up. If you need something outside these standard offerings—a non-standard thickness, a specific length, a particular finish—we can do custom runs too.

Installation

Simple, Fast, No Drilling Required Clamp installation is straightforward—no drilling into the panels themselves. The standard procedure: mount the rails (U-channel, C-channel, or aluminium rails) to the support structure, lay the PV panels on top, place mid clamps between adjacent panels and end clamps at the outer edges, then tighten the bolts. Each module requires two mid clamps, and each row requires two end clamps. Recommended tightening torque is 8-15 N·m, depending on module thickness and site conditions. Too loose, and panels will shift in the wind; too tight, and you risk damaging the module frame. Detailed torque recommendations are included with every shipment.

Applications

From rooftops to ground mounts, carports to BIPV mid-clamps and end clamps are used in virtually every type of PV installation. Distributed rooftop PV: Corrugated steel roofs, flat concrete roofs, tiled sloped roofs—clamps secure panels to the rails. Ground-mounted solar farms: Tens of thousands of panels connected panel by panel with mid and end clamps. What about carports? Same story—panels go on the carport structure, and the clamps do exactly what they always do: hold everything down tight.

BIPV is a bit different because the panels are actually part of the building itself. But guess what? You still need clamps. They're not optional.

And honestly, it doesn't really matter if you are using single-glass or double-glass modules, flat-lay or tilted—mid-clamps and end-clamps are the glue that keeps the whole array from falling apart. Without them, you've got nothing but a pile of loose panels.

Why Choose Our Products?

We won't sugarcoat it—Xiamen Honor Energy has been in the PV mounting business for years. We know exactly where things go wrong in a solar installation. Clamps may be small, but they fail more often than people expect. Loose screws, aged rubber, worn anodized coating—any one of these details can compromise the safety of an entire array. That's why we don't cut corners on materials: 6063-T5 aluminum, 304 stainless steel, and EPDM rubber—all proven, industry-standard solutions. Proper anodising means 20 years of outdoor service without issues. Our specifications cover the vast majority of panels on the market – 30mm to 50mm thickness, basically all covered. And if you need custom sizes, we can do that too. Clamps are small. But don't underestimate them. If you need reliable clamps that won't let you down, get in touch.