The Ultralight is great because you can screw it onto any 28 mm bottle top and have a hydration bottle. I keep a Swig Rig Ultralight in my car along with bottled water bottles. In case I forget to pack hydration in my pack. The pick-up hose is sized for a 48 oz wide mouth Nalgene. It is flexible enough that I can use it with a 32 oz bottle without trimming.
The hydration hose is "cut and put the modular connectors where you want them." The modular connectors are standard - so you can clip in an MSR in-line water filter. Or you can have a short hose, then clip into your favorite drinking tube. The drinking / bite value does not use a modular connector. It does have a slide switch to shut off water flow to the valve between uses.
The new style MSR Dromedary lids have a plastic cylinder inside that needs to be trimmed - so use the Swig Ultralight with its 28mm threaded fitting on the outside.
The Swig Rig Wide Mouth has a plastic washer plate with a barbed attachment for the hydration hose. Then a supplied lid with a hole is screwed on. The old style MSR Dromedary lids also work with the Swig Rig Wide Mouth.