Gitzo GS5321V75 / GS5321V100 Half-Bowl Video Adapter, Systematic Series 5

Same idea as the Series 2-4 inserts, sized for the big legs. These replace the flat top plate in a Series 5 Systematic casting with a half bowl, so a fluid head levels at the bowl rather than by shortening one leg on a slope. Series 4 aluminium tripods take the Series 5 part rather than the smaller one, which is the detail that trips people up when ordering.

The GS5321V75 is the 75mm bowl at 113 grams and 9.2cm across; the GS5321V100 is the 100mm bowl at 226 grams, sized for the heads a Series 5 leg set is bought to carry. Both are machined aluminium with the safety-catch ring, so swapping between a flat plate, a levelling base and a bowl on the same legs is a routine change rather than a careful one.