M30 concrete refers to Ready Mix Concrete (RMC) of M30 grade. This means it's a pre-mixed concrete blend, typically with a compressive strength of 30 MPa (Mega Pascals), and the price quoted is per cubic meter, according to a supplier in Hyderabad. The “M30” indicates the mix's design strength, while the “4100” likely represents the cost per cubic meter. The water quantity depends on the desired water-to-cement ratio. Concrete prepared with the M30 design mix ratio is suitable for constructing beams, columns, slabs, footings, and other similar structures.