1.High erosion resistance 2.Desirable breakage security 3.Shock-resistance 4.Security 5.SMC high quality pecifications(Hangzhou Jinmeng Road Facility Co., Ltd.)1.Anti-theft, the materials FRP/GRP ,SMC, DMC/BMC are not be used again.2.Anti-corrosion, the materials FRP/GRP ,SMC, DMC/BMC have high anti-corrosion.3. Long use-age life (Not less than 30 years). 4.Lighter than cast iron manhole cover5. ...