It has already been said in most of the reviews on this product, but it bears repeating.  Just pop in a bit and the spring mechanism locks in. pull back on the collar and it ejects.  So simple it is genius.  There are many other rapid load chucks available by other makers but for some reason they have all chosen to use a mechanism that usually requires two hands to operate and is not only more complicated in design, but not as efficient.  I have several of these made by just as many manufacturers, mostly because they are often packaged with a set of 1/4 inch shank bit sets, but the DeWALT is the only one I use everyday most of the others I own are still in the original case and mostly unused.