The Pro-Porta Trailer from Pro-Tainer offers multiple features specific to the portable restroom industry. All trailers have removable dividers that create space for ADA units and aluminum ramps for loading and unloading restrooms. The trailers also have a lock-down mechanism called the Pro-Latch that is part of the ramp system and automatically locks down the base of the restroom. 800-248-7761; www.protainer.com.