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Solder pallet, the basic unit of surface mount assembly, is used to form the solder pallet pattern of the circuit board, that is, a combination of various solder pallet materials designed for special component types. When a solder pallet structure is not designed correctly, it is difficult, sometimes impossible, to achieve the intended solder joint. There are two words for solder pallet: Land and Pad, and are often used interchangeably; however, functionally, Land is a two-dimensional surface feature used for surface mountable components, while Pad is a three-dimensional feature used for pluggable components. As a general rule, Land does not include PTH, plated through-hole. Vias are plated through holes (PTHs) that connect different circuit layers. A blind via is a buried via that connects the outermost layer and one or more inner layers, and only connects the inner layers.

Fiberglass is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass cloth. The plastic matrix may be a thermoset polymer matrix—most often based on thermosetting polymers such as epoxy, polyester resin, or vinyl ester resin—or a thermoplastic. Cheaper and more flexible than carbon fiber, it is stronger than many metals by weight, non-magnetic, non-conductive, transparent to electromagnetic radiation, can be molded into complex shapes, and is chemically inert under many circumstances. Applications include aircraft, boats , automobiles, bath tubs and enclosures, swimming pools, hot tubs, septic tanks, water tanks, roofing, pipes, cladding, orthopedic casts, surfboards, and external door skins. Other common names for fiberglass are glass-reinforced plastic (GRP), glass-fiber reinforced plastic (GFRP) or GFK (from German: Glasfaserverstärkter Kunststoff). Because glass fiber itself is sometimes referred to as "fiberglass", the composite is also called fiberglass-reinforced plastic (FRP). This article will adopt the convention that "fiberglass" refers to the complete fiber-reinforced composite material, rather than only to the glass fiber within it. Carbon-fiber-reinforced polymer is a similar composite material in which the reinforcement fiber is carbon fibers.