How much wireless range does the TP-211B have?

The TP-211B has 500ft of range line of sight.

This is tested in an open area, obstructions will reduce the range especially if there is concrete, walls, trees, brick, etc. in between.

Also, if the transmitter portion of the device is completely submerged in water, this will also reduce to the range. It is important to make sure the antenna is sticking out of the water.