Slightly smaller than MK-41, probably around 650mm
650mm is the same of the Mk-41. I should add that the HQ-16 is slightly physically bigger than the SM-2MR. The Mk. 41 might be longer however, but there seems to be a bit of inefficiency with the Mk. 41, so that the 4.75 meter SM-2 requires the Tactical 6.8 meter Mk. 41, while the 6.2 meter Tomahawk and 6.5 meter SM-2ER/SM-6 requires the 7.7 meter Strike Mk. 41. In contrast let's say, the 4.3 meter Aster 30 only needs the 5 meter Sylver VLS. I believe the AJK-16 might be around 650mm wide, but depth might be shorter than Mk. 41, probably around 5.5 to 6 meters or so, making it quite efficient, with the HQ-16 length around 5.2 meters. The U-VLS is also efficient, 6.8 meter HHQ-9 on 7 meter VLS, and 8.2 meter YJ-18 on 9 meter VLS.