Kettler Deluxe Door Chinning Bar.
A door chinning bar (also called a doorway pull-up bar) is a removable exercise bar that fits across the top of a door frame, allowing you to perform chin-ups, pull-ups, and other upper-body exercises at home.
This is an expandable (telescopic) type. It twists to expand between the sides of the door frame. Includes safety brackets that can be screwed into the frame.
Exercises that you can do include,
1. Chin-ups (underhand grip),
2. Pull-ups (overhand grip),
3. Neutral-grip pull-ups,
4. Hanging knee raises,
5. Leg raises, and,
6. Hanging stretches.