For vehicles with a higher step-in height, the double step is the perfect choice. It provides a comfortable and reliable platform for entering vehicles with 19" to 28" of clearance between the mounting surface and the ground. Series 32 - Motorhomes. 25-1/2" frame width, 24" tread width, 19-23" mounting surface to ground, 4-1/8 - 4-3/4" second step drop from mounting frame surface.