Mega system (italy) is an italian company specialized in manufacturing of air pollution control systems since 1981.all our instruments are based on the gravimetric method, so the official method, for the sampling of the particulate matter and the chemical polluttants in the workplace, in the environment and in the stack emissions. apis in particular represents the most advanced version of the automatic isokinetic samplers for stack emissions available in the market. apis is just a part of x1 series instruments dedicated to the isokinetic sampling in stack emissions.