These are level shifters/adapters (from left to right) for Mitutoyo, Shahe, and iGaging Absolute DRO+ scales. There won't be one for iGaging EZ-View scales, though.
The goal for these is to allow people to use a capacitive scale on the quill. Some benchtop mills come with scales with a data port. If not, it's easier to replace the factory scales with another capacitive scale than to convert the head to accept a glass or magnetic DRO scale.
TDA-4xx adapters that shipped after May 15th (with Firmware V3.2) already have support for the SPC and BIN6 protocols. Older adapters will receive an over-the-air update at some point (don't know the ETA yet).
I will have these listed in the store in a couple of weeks.
Regards
Yuriy