Fits like a glove - Kite Optics Silicon Jacket Apc 42

For what it is, this item is really overpriced. However if you've invested over a grand on a nice set of stabilized binocs then it is a small price to pay for a little extra protection. Obviously it fits perfectly since it is made by the Kite Optics company and goes on easily. If you never plan to take your binocs out in the wild then you can probably skip this. However if you are going to take them on your outdoor adventures then I would consider getting one.