Nilkatss 20mm Ball Mount Extension Arm (2-pack) — Dual-Socket Adjustable Aluminium with 360° Rotation

Nilkatss 2pcs 20mm Ball Mount Extension Arm is a dual-socket adjustable aluminum extension that expands and repositions devices attached to 20mm-ball mounts for precise, stable positioning.

If you need extra reach or finer angle control for a phone holder, action camera, or other accessory that uses a 20mm (0.787") ball socket, these two extension arms add flexible length and two fully rotating joints. Built from aluminum alloy with knurled locking knobs and anti-slip ball heads, the arms are intended for outdoor and automotive use where vibration and exposure can challenge lesser fittings. Confirm your mount is the 20mm size before ordering—this product is not compatible with 17mm, 22mm, 25mm or 1-inch (25.4mm) systems.

How does this extension arm change device placement?

The dual-joint design gives you two pivot points to move a device closer, farther, higher, or lower without changing the base mount. Each joint rotates 360°, letting you fine-tune tilt and orientation so the screen or lens faces exactly where you need it.

• Add or remove links to change overall arm length for reach or compact storage
• 360° rotation at both ball joints for unrestricted positioning
• Knurled locking knobs provide secure hold when tightened
• Anti-slip ball head helps keep phones and cameras stable during motion

Will this fit my existing setup and how do I confirm compatibility?

This product is specifically made for mounts that use a 20mm (0.787") ball socket. Before buying, measure your mount with calipers or a ruler—Nilkatss includes a visual measurement guide in the product images to help identify a 20mm ball correctly.

• Only compatible with 20mm ball sockets; not for 17mm, 22mm, 25mm, or 1-inch (25.4mm) balls
• Visual sizing guide included in images to assist measurement
• Use calipers or a ruler to confirm ball diameter before purchase

How durable and secure is the construction for active use?

Each arm is made from high-quality aluminum alloy to resist corrosion and handle off-road or exposed conditions better than plastic alternatives. The anti-slip ball head and textured knobs are designed to maintain grip under vibration, though heavier devices may require periodic re-tightening during long, rough trips.

• Aluminum alloy rods for strength and weather resistance
• Knurled knobs for positive, slip-resistant locking
• Anti-slip ball head for improved device retention
• Periodic re-tightening recommended for heavy or vibrating loads

How easy is assembly and what adjustments can I make?

Assembly is straightforward: attach the extension to your existing 20mm mount, add or remove linkage to set the desired length, then lock each joint with the knobs. The two joints let you pivot left/right, up/down, and rotate the device without interfering with vents or lines of sight.

• Choose length by adding or removing linkage and ball joints
• Both joints tighten independently for customized stiffness
• Compatible with phones, GoPros, and accessories that accept 20mm ball mounts
• Keep mounting surfaces clean and dry for best grip performance

Who this is for: riders, drivers, and outdoor creators who already own a 20mm-ball mounting system and want improved reach, adjustment, and stability for phones, action cameras, or accessories. It suits commuters who need better sightlines, drivers who want a tidier cockpit position, and hobbyists mounting cameras or lights where fine angle control matters. If your mount is not 20mm, seek the correct sized extension instead of this model.