Burt 1993, p. 234 A High-Angle Control System Mark I (HACS) was fitted with a director on the roof of the fore-top that replaced the high-angle rangefinder and the conning tower platform was enlarged to accommodate a pair of Mark V octuple mounts for the 40 mm QF 2-pounder Mark VIII gun Raven and Roberts, p. 250 The Mark V mounts could depress to −10° and elevate to a maximum of 80°.