It's a pool which produces an adjustable current which the swimmer swims against so he can get a workout doing laps without all that bothersome turning after each lap. It's like a swimmer's treadmill. Here's an ad for a popular brand. Notice that even the lifeguard is working with a laptop.
A lifeguard for a bathtub! There's no end to life's dangers, eh?
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-------------------- Women for Women International - For the special needs of women surviving war.
Kiva - Small loans changing lives around the world.
Bukavu Foundation - For the Panzi Women's Shelter & other programs in Eastern Congo.
Room to Read - Change begins with educated children.