The Step Extension is an amazing way to add a little bit of storage and utilize more floor in your sprinter plus we think it looks pretty awesome. The extension is made of aluminum and powder coated black while the trim is stainless steel powder coated black to match. We do the trim in stainless so it doesn’t dent from rocks etc that may be in your shoes. The top is open when it arrives. The builder will need to add the right thickness wood to match up with what ever floor/ flooring they are using. Please email for custom powder coat colors. Ships within a week.