AULUMU CS03 Titanium Mag Buckle Band Review: Galaxy Watch Ultra 2025/2024

Design and Build Quality

The AULUMU CS03 immediately stands out from basic third-party Galaxy Watch Ultra bands with its combination of high-density nylon and a titanium-alloy buckle. The black woven strap gives the band a rugged outdoor appearance that fits naturally with the Galaxy Watch Ultra, while the metal buckle adds a more premium finish. The buckle uses a DLC coating designed to improve resistance to everyday scratches and wear. AULUMU also uses a 1:1 integrated connector designed specifically for the Galaxy Watch Ultra, giving the band a clean connection with the watch.

Unboxing: What's Included in the Box?

AULUMU includes both a long and short strap in the package, which is one of the most useful things about the CS03. Instead of purchasing another strap size separately, you can choose the version that better fits your wrist. The long strap measures 205mm and is designed for 175–230mm wrists, while the short strap measures 165mm and is designed for 150–180mm wrists. The band itself is 26mm wide.

Magnetic Quick-Release System

The main feature of the CS03 is its magnetic quick-release system. Once you find your preferred fit, the magnetic buckle makes putting the watch on and taking it off much faster without having to completely readjust the strap every time. The magnetic buckle is combined with a hook-and-loop closure, creating a double-secure fastening system. In my testing, this was the feature that stood out the most because it makes everyday wear much more convenient.

Comfort for Daily Wear

The high-density nylon feels soft and flexible on the wrist and is designed to provide better breathability than a heavier metal-style band. AULUMU uses ultra-fine nylon fibers and a woven construction to help manage moisture during everyday wear and workouts. After using the CS03 for several days, I found it comfortable for regular activities such as working, walking, traveling, and wearing the Galaxy Watch Ultra throughout the day. It also keeps the rugged character of the Ultra instead of making the watch look overly casual.

Fit and Adjustability

The CS03 gives you plenty of flexibility when adjusting the fit. The hook-and-loop section allows you to fine-tune the strap instead of being limited to fixed buckle positions. The inclusion of two strap lengths is another advantage. The short strap supports 150–180mm wrists, while the long strap supports 175–230mm wrists, giving the band coverage across a broad range of wrist sizes.

Durability and Security

The titanium-alloy buckle is designed to provide a lightweight and durable fastening system, while the DLC coating helps protect the surface against everyday scratches. The nylon strap is also designed to resist pilling, snagging, and deformation under normal use. The magnetic buckle is not the only thing holding the watch in place. The additional hook-and-loop closure provides a second layer of security, which is particularly useful when wearing the Galaxy Watch Ultra during workouts and active use.

Galaxy Watch Ultra Compatibility

The AULUMU CS03 is specifically designed for the Samsung Galaxy Watch Ultra 2025 and Galaxy Watch Ultra 2024. AULUMU lists compatibility with Galaxy Watch Ultra 1/2 and provides a dedicated connector for the watch.

Care and Maintenance

The nylon strap can be rinsed with clean water and allowed to air-dry naturally. For deeper cleaning, AULUMU recommends using a small amount of neutral detergent and rinsing thoroughly. The company advises against machine washing, harsh acidic or alkaline cleaners, prolonged dampness, and direct sunlight drying.

Is It Better Than Samsung's Official Bands?

The CS03 does not necessarily replace Samsung's official Galaxy Watch Ultra bands because different bands are designed for different uses. However, it offers something distinctive with its magnetic quick-release system, titanium-alloy buckle, breathable nylon construction, and two included strap lengths. If you already like Samsung's Trail, Marine, or PeakForm bands, there may be no reason to switch. But if you want faster everyday wear, a different look, and a more convenient fastening system, the CS03 is an interesting alternative.