Wireless (preferred) or wired gate contact for Elk M1

Ive got an Elk M1 system installed and working. The other day, my landscaper left the gate open and our dog nearly ran away. Im looking to add that gate into my system just for the ability to tie it into my automation system.

Does anyone know of a weatherproof wireless contact for a gate that works with Elk M1? Wired is an option but not preferred.

Honeywell makes a wireless gate contact. You'll need the Elk M1XRF2H wireless receiver to work with it.
 
https://www.security.honeywell.com/product-repository/5816od