The NOMOS Tetra Basalt 440 represents the dark anthracite variant in the Tetra Origins collection. This model features a square case crafted from stainless steel, measuring 29.5mm on each side, and includes rhodium-plated hour and minute hands with a standout yellow seconds hand, all powered by the manual-winding DUW 4001 caliber. Among its counterparts—Ochra, Terra, and Salvia—Basalt is characterized by its deep hue.

Its sleek case dimensions are 29.5mm in width and height, with a slim profile of just 6.5mm and a lug-to-lug measurement of 40.5mm. The design includes a sapphire crystal on both the front and the back, secured by four screws. Unique to this model are its double lugs, enhancing the overall aesthetic while maintaining a low profile on the wrist; it is also water-resistant to 5 atm. The dial showcases an anthracite color scheme, featuring a blend of numerals and markers, a square minute track, and a small seconds display positioned at 6 o'clock. The sub-dial integrates anthracite with fuchsia and yellow accents, complemented by the vivid yellow seconds hand. The manual movement, the NOMOS DUW 4001, boasts a diameter of 10 ½ lignes, a height of 2.6mm, 17 jewels, and a power reserve extending to 53 hours. The movement can be admired through the transparent sapphire case back, and the watch comes with a beige vegan velour strap featuring an 18mm lug width.