The sturdy, colourful set includes three Cat® vehicles: a tipper, a wheel loader and a caterpillar, as well as two large containers: one for sand and a paddling pool. Two edges of the sandpit are channels through which water can run into the pool. The water tower and the six pipes also fit on it. Three are curved and three more are straight. They can also be connected to the large basin as a drain. To get over the water basin with dry tires, Theo Klein built a road ramp and also provided two warning beacons, two construction site signs, three pylons, six water bulkheads and a plug for the basin for the little builders.