No problem.
TF Z5 (or "Z1" in the pic) is 2x18650 but the pill is far from normal: Large & thick aluminum "star" works as a platform for the emitter and is screwed directly to a part of body (yes, anodized), which contains also the driver, which is way larger than 17mm => pretty non-moddable light, but quite good "as is". There's no cover for the star -> white star is totally below the emitter and gives more pleasant beam, especially when zoomed in.
The longer UF pill fits normal 17mm driver and emitter on 20mm star, being very nice for modder, but the pill is hollow and requires something (19.05mm alu rod) to fill it. Also the metallic ring around / in front of emitter makes the beam very ugly when zoomed in (see photo below)
Shorter UF looks very promising for modding, mods being the same as longer UF. At least my sample has a small white centering ring inside the metallic ring, which cuts the light, prevents some reflections, and makes the beam way better. It also zooms further out making the beam even wider in flood mode. I bet that after modding it will be the best out of these three..