The British convoy on 22 March 1942

Admiral Vian had a considerable force escorting a the convoy bound for Malta on 22 March 1942. They were organized in preparation for a surface action against Italian heavy forces:

1st Division:  destroyers Jervis, Kipling, Kelvin, and Kingston
2nd Division:  cruisers Dido, Penelope, and the destroyer Legion
3rd Division:  destroyers Zulu and Hasty
4th Division:  cruisers Cleopatra (Vian's flagship) and Euryalus
5th Division:  destroyers Sikh, Lively, Hero, and Havock
6th Division:  AA cruiser Carlisle and destroyer Avon Vale

Of these
Dido class cruisers:  Dido, Cleopatra, and Euryalus (designed for 10-5.25in)
Arethusa class cruiser: Penelope (6-6in)
C class cruiser as AA ship: Carlisle (8-4in AA)
Tribal class destroyers: Zulu and Sikh (designed for 8-4.7in)
J and K class destroyers: Jervis, Kipling, Kelvin, Kingston (designed for 6-4.7in)
L class destroyer: Legion (designed for 6-4.7in)
H class destroyers:  Hasty, Hero, and Havock (designed for 4-4.7in)
Hunt class Type II destroyer: Avon Vale (4-4in AA)