Ripjaws V is G.Skill's low-profile heatsink line for DDR4 — flatter than the brand's taller Trident Z kits, chosen as much for clearing large air coolers as for anything printed on the spec sheet. It has stayed in the catalogue long enough to span several distinct speed bins under one name.
That spread shows up directly in the listings: 2×8GB at 3000 MT/s CL16 is one point in the range, and other kits carrying the same name land at noticeably different timings. Two sticks both labelled Ripjaws V are not automatically interchangeable — match 16GB and the rated speed to what your motherboard's memory support list actually shows before buying a second kit to pair with one you already own.
All of it is DDR4 UDIMM for standard desktop boards. It needs unbuffered, non-ECC support, which covers essentially any consumer desktop platform built for DDR4.