S-350 is the most popular concrete capping products of Capstone Series. S-350 provides the best balance of working ability and strength performance for concrete capping. The water and gypsum ratio for S-350 is recommended to be 23-24%. After simply mixing with water, the gypsum can be used immediately and will fully harden in approximately 30 minutes. with strength reaching over 350 kgf/cm2, equals to 5000psi.