This is the most common design of pallet racking used. The standardized "teardrop" connection design makes the uprights and crossbeam interchangeable with those from other manufacturers. This design is very versatile and the boltless design simplifies reconfiguration of beam levels. The alternative to boltless racking is structural pallet rack which is assembled with mechanical fasteners (usually bolts) and may offer higher capacities. Structural pallet racking is also sometimes designed into the structure of the building itself supporting the roof and eliminating the need for I-beams.