The new patented Monolith® underground enclosure (US Patent #11,931,930) is the market's strongest and most durable.
It combines fiber-reinforced polymer with polymer concrete to create a smooth one-piece enclosure (Monolith®) that exceeds T22 load testing. It also incorporates a tapered design (a first for polymer enclosures) that will allow installers more interior volume and can be stacked, which will allow for a smaller shipping footprint.
It is lighter than traditional polymer and fiberglass enclosures.
Source: www.newbasis.com