My Dewalt Powered Mega Phone

In this video I attache a Dealt Battery to an 8C cell megaphone.
Below are the two items needed, I imagine you already have the soldering gun, solder, and tape.
https://www.amazon.com/dp/B08FCNP2R6?psc=1&ref=ppx_yo2_dt_b_product_details
https://www.amazon.com/dp/B08F4WRKML?psc=1&ref=ppx_yo2_dt_b_product_details