The DYER FIBERGLASS 'D' SERIES is a one-piece female-molded series of enclosures that consists of (12) basic sizes from the D-103 to the D-303. These enclosures are used for a variety of jobs in any industry where equipment must be protected from the environment--or the environment protected from the equipment. Typically, DFI's customers have used the 'D' Series covers to protect wellheads, small tanks or pumps, small-to-medium sized lift-stations, and small-to-medium sized blowers or compressors. The 'D' series covers have thermal insulation values ranging from R-14 to R-19, and sound reduction values ranging from 5 to 12 dBa (averaged across all frequencies and at all points on the cover.) Each basic model in the 'D' series has a number of option packages. The WHOLESALE OPTION package is sold primarily to customers who keep a stock and sell to the public. Each cover is constructed of a fiberglass composite laminate made with rigid thixotropic resins and 30% chopped strand glass to a thickness of 1/8". Each cover is insulated with a 2 lb. polyurethane foam, resulting in an R-14 thermal insulation value--and about 3-5 dBa in sound reduction. The outside surface is a polyester gelcoat, usually white, with a UV inhibitor. The enclosure is attached by hardware to an FRP open-base flange with the bottom wide enough to anchor to a surface. This package includes polycrosslink (plastic) hinges; stainess steel nuts and bolts; one 7" cast aluminum handle; and a 30 lb. spring-loaded latch (also known as a 'hook'.) On the smaller covers, our customers often prefer to use hooks and handles on each end, so that they can lift the cover straight off their equipment without tilting it back. We offer this modification at no extra cost. The STAINLESS STEEL OPTION package substitutes a pair of stainless steel hinges (3 hinges on some larger models); a stainless steel hasp; and up to (2) 6" adjustable aluminum vents. On some smaller covers, we will substitute an extra hook, handle and lockable hasp for the hinges for the customer, at no additional cost. Other options, such as a continuous stainless steel piano hinge or larger vents, are available at extra cost. In many respects, this is our 'standard' option package. The HEAVY DUTY OPTION package adds 1/3 extra resin and glass to the SS Option package. Insulation values increase to R-19, sound reduction moves into the 8-9 dBa range, and the cover itself is more resistant to damage. This is the package we recommend for covering small blowers, or small engines; or if the equipment is located in the northern US, Canada, Alaska, or similar climates. The HEAVY DUTY SOUND OPTION package is the same as the HD Option package, but replaces the sprayed-in polyurethane foam with a dual-purpose accoustical foam, which retains the thermal insulation values but improves sound attenuation to 10-12 dBa.