Does anyone remember this modular breadboarding system

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Hello,

I am trying to remember who made a certain modular breadboarding system.
The system consisted of a long grey plastic tray, which could be connected
to others side by side. Colored mini-breadboard modules could then
be slid into these trays.
I believe it was made by some fairly well known vendor, and was frequently
seen in electronics distributor showrooms.

Does anyone have any idea what this might have been?

Thanks