What is "Universal Modifier toolkit"

ALLIEKATBLUE

This product makes reference to this. Also are new iray shaders required for the updated DAZ 4.9.4 or whatever. I really don't want to have to buy new shaders.

https://www.daz3d.com/uber-iray-sheer-silky

Daywalker Designs

I believe this simply makes use of the new features included in the version of Iray included with 4.9.4.

Richard Haseltine

Reading the dscription it means modifiers - here lace opacity maps I think - that can be used with "any" shader (or at least, any from this series by Traveler).