In terms of armament, "Waikato" was a fully armed Batch 2 "Leander". With Mk 6 twin 4.5-inch guns, a Seacat GWS22 point defence missile, Limbo anti-submarine mortar and Wasp helicopter. She was identical to the Royal Navy "Leander"s of her group, with 965M LRAW and 177 hull and 199 Variable depth sonars, while her half sister, HMNZS "Canterbury" was a larger improved "Leander", completed in 1971, with a more automated and remote controllable steam plant, a frigate potentially capable of updating with long range bow sonars and Seawolf missiles. HMNZS "Canterbury" a similar sensor and weapons to "Waikato", because New Zealand could not afford the better screen displays and faster processing systems fitted to 1971/2 RN "Leander"s, and because cost margins of the last group of the "Leander"s were tight, it did not receive the more modern sonar and ECM/ESM of the last two Royal Navy "Leander"s. The "Leander"s were very expensive for New Zealand and the cost per ton, is just as high as the U.S. Navy , which were poor seaboats. Some Royal Navy "Leander"s eventually carried bow sonars in the 1980s with the range of power of AN/SQS-26, and all recently refitted clean bottom "Leander"s and "Rothesay"s were silenced more effectively than early 1980s Type 22 frigates.