FLT-DLY is a filter and a delay combined into one.
But this is no ordinary filter. This filter is a Resonant Bandpass coupled with a 2-Pole Highpass and a 2-Pole Lowpass with the ability to mix between the two. Effectively, it gives you a Peak, Highpass and Lowpass Filter that can be blended between each other. The Delay also adds a slight modulated variation in the stereo field.