The name says it all, IDA is a 2hp Compact Discrete VCA.
Almost all eurorack VCAs use the same opamp, which is very effective for CV but a little bit clean for audio signals in our estimation. This VCA is fully discrete and features no op amps, giving it a different frequency response from usual eurorack VCAs, slightly warmer and deeper. A VCA like this can be great to help texturally differentiate between two synth voices in a system.