Modularity is the ability of different components (modules) to fit together in a variety of ways and combinations. Modularity in glasswork depends on standardized joint sizes. The best example of modularity in GRAV® products is the STAX® line. Every design feature and major component of a water pipe - bases, percs, and mouthpieces - are built separately in the STAX® collection and interlock via 34mm joints, allowing smokers to build their own water pipe using STAX® modules.