Door switch with wired external magnet contacts for metal mailbox

[djh_wolf (Daz)]

Dumb door and window sensors (UK)

Hi, I have a couple of zwave contact sensors but they’re far too expensive to add to every door and window. Just wondering if there’s a cost effective way to hook up a stack of dumb wired contact sensors and have them usable in Smartthings/webcore etc? I believe the fibaro implants allow 2 (?) maybe, but that route really isn’t cost effective. Much appreciated!

Maybe this will help.