Manamo (Manufacturas Nacionales de Modelismo) was founded in 1941 by a Mr. Argimón, who worked with a small group of craftsmen (amongst whom were Olive Ollé, his son Norberto Ollé  and Enrique Pareto – the last later finding fame as one of the associates of Microtren, producers of brass-built H0 scale models) to produce what at that time could be termed scale models, all in 0 gauge. The range consisted of at least 12 steam-outline locos, ranging from a simple, 23 cm long 0-4-0T to an impressive 4-8-4T  at 60 cm and a 4-8-2 measuring 62 cm. The largest steam loco was a streamlined 4-6-4 at 68 cm. Then there were 2 electric-outline locos (a simple 0-4-0 centre-cab and a large, 40 cm, 4-6-4), 2 self-propelled electric and diesel bogie coaches and a 2-car EMU. All locos were powered by a 20-24 V AC motor for 3-rail operation and could be had with either manual or remote-controlled reverse.

Rolling stock consisted of an extensive range of goods wagons: four-wheeled flat wagons loaded with an anti-aircraft gun, a search light, motor cars, oil barrels, logs, crates and sacks, and wine barrels, plus low and high sided wagons, covered wagons, hopper wagons and crane wagons. Then there were four-wheeled and bogie vans, and bogie flat wagons, tank wagons and cattle vans. There also was a number of bogie and four-wheel passenger and bagage cars, as well as accessories:  stations, platforms, a station canopy, freight sheds and freight platforms, watchman’s huts, lamp standards, barriers, a water tower, bridges, telegraph poles, signals and signal bridges, tunnel openings, figures, cargo like crates, barrels, wool bales, sacks and trunks and even catenary. Track was available in three qualities: “via standard”, tinplate rails with 3 tinplate sleepers for straight sections, 4 for curves, the “via modelo”, steel rails with 12 tinplate sleepers per length and which resembled the Märklin Modellgleis or Model Track and the “via gran modelo”, brass rails with 10 wooden sleepers per length, mounted on battens, which was akin to the British LMC and Milbro track.

For most of the existence of Manamo wood was used to build coaches, wagons, vans and stations and other accessories, while the steam outline locos were made of tinplate. Around 1960 Manamo also produced some coaches in etched brass, while some goods rolling stock was made entirely of tinplate. As H0 gained popularity in Spain from the mid-50s onwards, demand for 0 gauge declined and in 1963 Manamo closed its doors.