The qualities of the Natural Rubber allow the user to clean more efficiently on wet surfaces. The Urethane is also beneficial to own as it has been proven to be extremely durable.
15" Squeegee with Rubber Insert: Used with a wet/dry vac. Flexible insert makes wet clean-up easy. Glides well on wood floors as well as concrete. Imagine a shower or window squeegee... that is the type of flexibility you have with this rubber insert.
15" Squeegee with Urethane Insert: This squeegee has a stiffer, clear insert that helps move water as well as block wet from spreading while you clean. Imagine an auto squeegee like at the gas station. The squeegee part is thicker and a little more stiff, but still flexible enough to maneuver on hard floor. Ideal for concrete, tile or other stone surfaces.