The radiator itself is pretty straight forward. It's relatively thin at 27 mm (only slightly thicker than a standard fan) and has holes for mounting and attaching the two 120mm fans. The aluminum fins are folded back and forth thousands of times to create a radiator assembly that resembles that of a car, and the liquid will be pumped through this array of fins where the fans will push the heat out of the case. One end contains the reservoir and fill port (which warns against tampering if you care about your warranty), and the hoses are anchored securely in place to the reservoir itself.
The primary differentiator between the Seidon 240M and the handful of nearly-identical 240mm all-in-one liquid coolers is its pump. The pump housing and base are much thinner, due partly to Cooler Master choosing a better pump, and largely because of what Cooler Master calls the "UltraFine Micro-Channel." The base has channels machined into it, which does the same thing as a heatsink or the radiator does; it creates more contact surface area for more rapid heat dissipation. Cooler Master also claims these grooves also helps "optimize water flow," and my guess is that these channels act as tiny guide vanes straightening out the flow of water, preventing it from swirling as it enters or leaves the pump.
The base itself is all-copper and is machined to be exceptionally-flat, but it isn't polished to a shine. The top of the pump has Cooler Master's logo cleanly inlaid next to an industrial-looking design on its smoke-grey cover. The screw holes have a small groove underneath them which makes placing the mounting brackets quick and easy, and helps support the bracket for a sturdy fit.