Martin Maryland and Baltimore light bombers

The Martin 167 A-3 was a light bomber designed for a US Army bomber contest of 1937-38, but that entered combat with the French Armée de l’Air, before becoming the basis of the RAF’s Maryland and Baltimore bombers.
The Martin Maryland was a light bomber originally developed to satisfy a US army specification and which entered British service after the fall of France.
The Martin Baltimore was a light bomber developed by the Glenn L. Martin Company from its Model 167 Maryland to satisfy a British specification.
We provide a list of squadrons that used the Martin Baltimore light bomber
The Martin Baltimore I was a light bomber developed from the earlier Maryland by increasing the width and depth of the fuselage and installing more powerful engines and more guns.
The Martin Baltimore II differed from the Mk I only in that it was delivered with two 0.30in Browning machine guns in the rear dorsal position in place of the single gun of the Mk. I
The biggest problem with the earlier versions of the Martin Baltimore had been the poor rear guns – two hand operated Vickers “K” guns which proved to be difficult to use in combat – and so the Baltimore III was equipped with a powered gun turret
The Martin Baltimore IIIA was the first version of the aircraft to be provided under lend-lease, and was armed with a different turret to the Baltimore III.
The Baltimore IV was very similar to the Baltimore IIIA, differing only in some internal equipment.
The Baltimore V was the final version of the aircraft to be produced, and differed from the earlier versions in using more powerful Wright R-2600-29 Cyclone engines.