It's a K2 Oz-M. It's all thermoplastic CF made by K2 and Easton. The main triangle is produced by K2 and is a 3-piece monocoque structure with two halves bonded to an internal reinforcement spine all made out of CF. This construction is similar to what Cannondale used for their CF bike except that Cannondale used an aluminum and then later magnesium internal spine. The K2's main triangle was produced in Vashon, WA but I'm not sure where the swingarm and fork legs, which were produced by Easton, were made. The bike was made for only two years. It was offered in two main trim levels and a superlight version. In 1998, it retained the Pro-Flex name and was called the Pro-Flex 4500C and the Pro-Flex 5500C. In 1999, there were some minor improvements, a slightly different subdued finish and the names were changed to the Oz-X and Oz-M respectively. An Oz-M Superlight was also added which had all the fasteners and coils replaced with titanium equivalents. My bike is a modified Oz-M. The stock rear shock on the Oz-M is a Noleen NR-2. I replaced it with the NR-5 to match the front shock in the CrossLink-CS fork and changed the spring to titanium to give it a smoother feel.
Not many companies produced thermoplastic CF bikes. Most CF bikes (road and mountain) are made using thermosets. Mantis and GT worked on a joint project to create the earliest thermoplastic bike I believe with the Mantis Screaming V. This is the bike I really wanted but very few were ever produced before Mantis closed up shop and they were/are quite rare and expensive. GT itself took the technology to produce a limited number of CF-based STS/LTSes back in 1995 which was a CF version of their XCR. They later followed up with a second generation thermoplastic bike called the XCR 2000.
K2/Pro-Flex started sticking CF swingarms and forks on their aluminum Evo frames around 1996 and then produced a full CF frame based on the Evo geometry for 1998. While they performed well, the cost and labour involved to produce these things were so high that they discontinued them after only a two year run.
While many people in the roadbike community were surprised to see Cannondale come out with a full-CF road frame, it should be noted that Cannondale had been using CF in some of their MTBs for a while and they introduced the thermoplastic Raven back around the same time as K2 introduced the Pro-Flex 4500C/5500C in the 1998 model year I believe. Cannondale actually stuck with the Raven longer. I think they terminated production of that frame in 2001 or 2002. Neither the GT nor Cannondale bikes were full thermoplastic CF though. They all used aluminum rear triangles and swingarms. To my knowledge, only Mantis and K2 ever made full thermoplastic CF bikes. You can find out more about the K2/Pro-Flex CF bikes on the
K2/Pro-Flex Riders Group webpage.