This kit allows creating a dual fan setup using any combination of our High Output Single RAD Fans, the 16212/18212 (12"), the 16214/18214 (14") and the 16217/18217 (17"). Kit includes 2 each triangular brackets that tie the fans together at the outer shroud, 2 each mount brackets and 4 screws. All other mounting hardware comes compete with the fan(s).