FRP Manhole cover high quality and good service BS EN124 ISO9001:2008 & SGS Certification Burglarproof & Never rusted Composite manhole cover:Hunan Timelion Composite Materials Co., Ltd., established in 1999, is the largest composite manhole cover manufacturer in China. We specialize in producing and supplying composite material (FRP/GRP) manhole covers, rain gratings, tree gratings, flower pots, ...