This spring reverb module is part of my Eurorack series. It drives a reverb tank and has two inputs, controls for dry/wet and resonance.
You need a separate reverb tank; it is not included in the kit. This module is well tested with the Accutronics AMC2BF3/Intellijel small reverb tank but should work with any tank that has an input impedance of 150 ohms or higher.
More details and assembly instructions at https://polykit.rocks/spring
Please note the product safety information