This 1 of 1 Coyote Brown IMS Flex prototype is built from 500D nylon. We built it during the design and development phase of IMS Flex and did laser cut the Drink Tube Routing Ports. However, this was an experimental piece to figure out how strong the nylon would be after being laser cut for this type of non-structural application. Therefore, it does not have the Laser Cut Reinforcements found on the production version IMS Flex (now retired). These non-reinforced Drink Tube Routing Ports still function, but they are not as strong as the production variants with reinforcement. All other aspects of this IMS Flex are the same as production: YKK Zipper, attached MOLLE webbing, etc.