Spinner - Collets - Plastic Rings on a Tree

Question: My VMAR ARF model came with a very complete set of Hardware & Accessories. I have one item that I am not sure about. Its a plastic "tree" with 8 rings on it. They look like they are intended to be a spacer or collet. What are they for?

Answer: These are collets for adapting VMAR spinners to various crankshaft diameters. Most VMAR ARF's now come with metal spinners that have a brass collett and generally do not require the plastic collets. But there may be some modelers who need to adapt a spinner to their crankshaft so we have included the 8 plastic rings (collets) with some models. In most cases they will not be required.