Tricky Topsy Turvy Bottles

Looking for a great comedy prop that allows both you and the volunteer to have great fun on stage?
Topsy Turvy Bottles gets a great reaction every time.
The Effect: 
The volunteer and the performer each have a metal cover and a bottle. Both covers are shown empty and then placed over the bottles. They are turned upside down several times, the volunteer following your every move. However, when the covers are raised the performers bottle is always upright and the volunteers bottle is always upside down. Repeat the process as often as they want!
Great comedy potential, and your audience will roar with laughter as your confused spectator tries so hard to follow you.
Best of all it is very very easy to do. Allowing you to concentrate on your presentation and the volunteer.