This connects to the Solo accessory bay.

Can be used with or without a small breakout board.

Takes one 9G servo.

The optional hardware pack consists of four M2x10mm screws

Base price is for printed part only. Select desired options based on your need.

Recommended breakout board is the Brownie Board Nano with male headers and no mounting holes. (breakout boad is not required but can be handy in some applications)
https://store.brownieboards.com/product/3dr-solo-nano-breakout-board/

*requires soldering for PWM signal which is described HERE thanks to Hackster.

Here is an installation video