Every model of the Skim-A-Round is designed to drastically increase water surface velocity & pull debris from a greater distance but, each Skim-A-Round model can be used to solve a different issue
Skim-A-Round "Original" 
Skim-A-Round | The Floating Pool Skimmer
Extra or Replacement Skimmer
Traditional wall skimmers rarely provide enough suction to pull debris in from across the pool. Skim-A-Round can be added to the pool or spa as an extra skimmer, or even as a replacement skimmer.  Just plug Skim-A-Round into the vacuum line, or even into the bottom hole of an existing wall skimmer.  Since the openings in the Skim-A-Round are smaller than the opening in the traditional wall skimmer, the surface water moves through the Skim-A-Round at a higher velocity, creating more suction force, allowing it to pull debris in from a greater distance.  Within 5 minutes, Skim-A-Round will be out toward the center of the pool, keeping your pool surface free of debris
Protect Your Pool Pump
Normally, if a swimming pool loses water due to a leak or evaporation, water will need to be added to the pool immediately, to prevent the pool pump from running dry.  Since Skim-A-Round floats on the pool surface it will follow the water level, so re-filling the pool is no longer an emergency.

Skim-A-Round "As Vac Attachment"
Skim-A-Round | Floating Pool Skimmer
Skim & Vacuum At The Same Time
This model provides the ability to attach a fully functional pool skimmer to your pool vacuum, creating a MOVING skimmer. Now, wherever the pool vacuum goes, Skim-A-Round will follow, simultaneously cleaning the pool surface.

Skim-A-Round "All-In-One"
Transform your existing wall skimmer, while eliminating the need for a "weir/flap"
This model utilizes the same physics principals as the others to increase surface water velocity; but it does this INSIDE YOUR EXISTING SKIMMER.  This model does not travel around the pool, but it will significantly reduce the amount of debris in your pool. Also, this model floats above the water line when the pump turns off, so it traps debris from entering back into the pool.  So you no longer need the weir/flap attached to the front of your existing skimmer housing.