This article presents a new ultrasonic massflow meter that has only two transducers. The mass flow is inferred from volumetric flow and density. Each of the transducers is an ultrasonic densitometer based on a design by Lynnworth. The flow is estimated by the transit time difference of the sound pulse between the up and down-stream acoustic propagation. Beyond presenting the meter, this article does looks at its signal at zero flow to address the issue of reciprocity in transit time flow meters which is in contradiction with the theory of transit time flow meters.