https://www.canopyair.com/freetrial?coupon=canopy2018Through the free trial landing page,
click Shop 1'' Filters,
Select your width/height of your desired air filter (leave the depth at 1''),
Select your frequency of receiving a new air filter shipment,
Enter in account/billing and payment info, $15 off promo code CANOPY2018
should automatically be applied,
Place order