Unmounted (adjective)

1. Not placed or fastened on something.
2. Not having been put on a horse or a bicycle.
3. Not assembled or installed.

Origin:

Late 16th century, from un- + mounted.

Examples:

1. The unmounted picture was still in its frame.
2. The unmounted tires were in the trunk.
3. The unmounted engine was lying on the ground.
4. The unmounted shelves were in the box.
5. The unmounted hardware was in the bag.