A metering assembly, comprising: a measuring element comprising: a cover including angled mounting holes and an underside cavity, a measuring channel coupled to the cover adjacent the underside cavity to form a gap between the cover and the measuring channel, the measuring channel including a seal ring secured to an inlet end of the measuring channel, an electronics module including at least one pair of ultrasonic transducers for measuring a flow of a fluid flowing through the measuring channel, and a processor to calculate a flow value from the pair of ultrasonic transducers, wherein each of the ultrasonic transducers is configured to sit in one of the angled mounting holes and to transmit an ultrasonic signal at an angle onto an acoustic reflector, and the acoustic reflector is mounted to the measuring channel, wherein the acoustic reflector reflects the ultrasonic signals between the pair of ultrasonic transducers in a V-shaped measurement path; and a main case that includes: a main cavity to receive at least a portion of the measuring element, a flange surrounding a top of the main cavity, the flange configured to support the cover, an entry section that transitions a flow path from a first cross-sectional area to a second cross-sectional area, and a machined surface adjacent the second cross-sectional area and facing the main cavity, wherein, when the measuring element is installed in the main cavity, the seal ring is configured to press against the machined surface to form a fluid-tight seal, and wherein the gap between the cover and the measuring channel is configured to release air through a bleed hole from the underside cavity. a measuring element comprising: a cover including angled mounting holes and an underside cavity, a measuring channel coupled to the cover adjacent the underside cavity to form a gap between the cover and the measuring channel, the measuring channel including a seal ring secured to an inlet end of the measuring channel, an electronics module including at least one pair of ultrasonic transducers for measuring a flow of a fluid flowing through the measuring channel, and a processor to calculate a flow value from the pair of ultrasonic transducers, wherein each of the ultrasonic transducers is configured to sit in one of the a cover including angled mounting holes and an underside cavity, a measuring channel coupled to the cover adjacent the underside cavity to form a gap between the cover and the measuring channel, the measuring channel including a seal ring secured to an inlet end of the measuring channel, an electronics module including at least one pair of ultrasonic transducers for measuring a flow of a fluid flowing through the measuring channel, and a processor to calculate a flow value from the pair of ultrasonic transducers, wherein each of the ultrasonic transducers is configured to sit in one of the angled mounting holes and to transmit an ultrasonic signal at an angle onto an acoustic reflector, and the acoustic reflector is mounted to the measuring channel, wherein the acoustic reflector reflects the ultrasonic signals between the pair of ultrasonic transducers in a V-shaped measurement path; and a main case that includes: a main cavity to receive at least a portion of the measuring element, a flange surrounding a top of the main cavity, the flange configured to support the cover, an entry section that transitions a flow path from a first cross-sectional area to a second cross-sectional area, and a machined surface adjacent the second cross-sectional area and facing the main cavity, a main cavity to receive at least a portion of the measuring element, a flange surrounding a top of the main cavity, the flange configured to support the cover, an entry section that transitions a flow path from a first cross-sectional area to a second cross-sectional area, and a machined surface adjacent the second cross-sectional area and facing the main cavity, wherein, when the measuring element is installed in the main cavity, the seal ring is configured to press against the machined surface to form a fluid-tight seal, and wherein the gap between the cover and the measuring channel is configured to release air through a bleed hole from the underside cavity.