The RPS-001 is an assault rifle manufactured by Rung Paisarn Heavy Industries of Thailand. It is an adaption of the Czechoslovak vz. 58 with components from the M16A2. It was introduced during the Advanced Combat Rifle trials. Surprisingly, this weapon is of excellent quality and performance.
In the 1990s, the Thai Army was looking for a replacement for their then-current, but severely obsolete, service rifles, such as the M1 Garand and M1 Carbine. The army was still deciding whether they wanted to use weapons from other countries or develop their own weapons. On hearing this, Rung Paisarn Heavy Industries, the largest Thai small arms producer at the time, immediately went to work, with their designs culminating in the RPS-001. The weapon was rejected as the chief designer faced some legal troubles involving illegal arms sales, with rumors spreading about him trying to sell his weapon to Iranian and North Korean soldiers. Due to these rumors, the chief designer was arrested and has remained in prison since, which has led to the RPS-001 being rejected. Only a few hundred rifles were made.