Close Focusing Adapters

Some of my favorite vintage lenses just don't focus close enough for my needs. So, instead of buying a plain old dumb adapter and being frustrated by the inadequate closest focusing point, I usually purchase a close focusing adapter. This type of specialty adapter allows me to focus closer. I prefer close focusing adapters to close-up filters, reversing rings, and extension tubes because they are: built into the adapter, always available, and they don't degrade the image!