It is used as a reinforcing agent for many polymer products ; the resulting composite material , properly known as fiber-reinforced polymer -LRB- FRP -RRB- or glass-reinforced plastic -LRB- GRP -RRB- , is called `` fiberglass '' in popular usage .

It is used as a reinforcing material for many polymer products . The proper names are fiber-reinforced polymer -LRB- FRP -RRB- or glass-reinforced plastic -LRB- GRP -RRB- .
