The CVS4200C is a composite, stationary water sampler designed for indoor use. All samples are combined into a single container. The sampler uses reliable, long-lasting, vacuum technology. This sampling method results in faster sample draws and less disturbance of the sample contents. There is also less wear on the tubing, resulting in less frequent maintenance. The CVS4200D differs from the CS4200C in that it is a discrete sampler that places each sample into a separate container. Vacuum technology benefits over peristaltic pump samplers: Accurate sample volumes Rapid transport velocities mean more-representative samples Less disturbance of sample Minimal wear on the tubing, resulting in less-frequent maintenance Reduced cross-sample contamination