HomeNonmetallic Enclosures Fiberglass Enclosures Fiberglass enclosures are well suited for a variety of applications and are designed to insulate and protect electronic components in both indoor and outdoor applications and environments. Polycarbonate Enclosures Polycarbonate enclosures are an aesthetically pleasing and durable alternative to similar fiberglass enclosures. 1 Product 7x4 to 9x4 – Fiberglass Enclosures