
Hi Ed! The total length is 4". The "length installed", which does not include measurement of the 1" adjustable clamp, is 3". Please see page 11 of the following for a diagram: https://www.z-flex.com/information_centre/zflex/02Z-Vent%20Special%20Gas%20Vent%20System/50Z-Vent%20Appliance%20Adaptors%20Dimensional%20Data.pdf
Yes, it is.