Accessories and Documentation
Looking closely at the parts bags, they are marked with letters and the manual tells you what parts, from which bag are needed to mount your system for each processor type. The coiled plastic above the parts bags is to wrap around the tubing and it reinforces the tubing so it does not kink when bent at extreme angles.
The PW 850i manual is actually a book that gives a detailed description of the components, their use and how to mount them. Since many first time water cooling enthusiasts choose to purchase an all-in-one kit, it is important to have good instructions available. The 850i gets the tick of approval here.