High strength plastic pedal replaces existing pedal and allows foot to be strapped into pedal for a stable pedaling platform. Price is per pedal.  For Adult Size Shoes. 

The thread of the pedal is 9/16" - check your bike or trike for compatibility/fit. If you need the 1/2" size instead,

From heel cup to front of pedal is 10 inches.  Width is ~4 inches at narrowest spot.  Heel support is 4 inches tall from platform.

On indoor exercisers, the weight keeps the pedal parallel to the ground to make it easier to put your foot on the pedal.

Removing the weight positions the pedal heel down, which is sometimes preferable on an outdoor recumbent bike.

Weight is easily removable with four screws.