For those who haven't got Facebook, this is the info I managed to collect:

The Taiwanese (Republic of China) M1 is one of the most intriguing and interesting of all the M1 helmet variants. However, information regarding the supply and use of M1 helmets and M1 clones by Taiwan is scarce and fragmented. Their origin date back to the end of the Sino-Japanese War (1937-1945) and the Chinese Civil War (1946-1950) when the US supplied equipment (including M1 helmets) to aid the Chinese fighting the Japanese and, later, to aid the Republic of China after its retreat from mainland China onto the island of Formosa. Taiwan had a substantial number of these US-manufactured M1s and they became the standard helmet for the Army, Navy and Marines. At one point, these US helmets were replaced by a first generation of M1 clones manufactured by Taiwan. These came with an inner liner similar to the thermoplastic liners of Danish M48s and green cotton chinstraps similar to those on US M1s. However, the most interesting modification to the Taiwan-made M1s came in the mid-1990s, coincidentally around the time the Taiwanese Army and Marines acquired Taiwanese-made Kevlar PASGT clones. These second-generation Taiwan-made M1s lack the inner helmet found on US M1s and European M1 clones. Instead, these M1s were issued with a near-exact replica of the German Schuberth Modell B Typ 825 plastic liner system, held in place by three rivets welded on the inside of the helmet shell and by flat hexagonal nuts. These black liners lack the plastic net found on German Modell B Type 826 helmets. Instead they have a square patch of Velcro, riveted directed into the plastic, which holds in place a thick circular cushion which makes the helmet very comfortable to wear. The adjustable liner on this particular helmet has the marking L (large) and a patent number (PAT.138813). The sweatband is black, unlike the brown ones found on the German helmets. The shell is quite heavy, painted in matt dark green with a turquoise-coloured undercoat. Sand was added to the paint. The edges of the shell are covered with a rear-seamed stainless-steel ring, similar to that on US M1s, to conceal the sharp edges of the shell. There seem to be no visible markings or stamps on the shell. The two-point, green nylon chinstrap is attached to two swivel bails and the chinstrap is clipped in place by means of a rather-flimsy black quick-release plastic buckle. It also comes with a double chin-rest, with one strap being made of cotton. The cover on this particular helmet has the standard ROC leaf-pattern camouflage pattern, quite similar to US M1948 ERDL pattern. It also has a camouflaged elastic band, with two coloured ‘cat’s eyes’ affixed on it, one at the front and another at the back. These can be either red or blue, depending on how you place the elastic band. This configuration is still used during training. This M1 second-generation variant is still used by the Taiwan Navy, Air Force, Reserve and academies.