The no-frills A40HP Rockmaster Concrete Pump is for contractors who need a high-performance concrete pump on a very tight budget. It can pump pea-gravel mixes, ¾-in. blend mixes, 1-in. big rock mixes, and low-slump shotcrete mixes. This pump is unique because it offers high horsepower (82), high concrete pressure (1172 psi), and high volume (40 yds/hour) for a very low price ($51,450 MSRP). REED Concrete Pumps.