T' 18mm Engine Retainers were designed t' be used with t' Aerotech 18mm reloadable rocket engines, nay t' standard single-use motors (from Estes, arrr, Quest, Apogee, me bucko, or Aerotech). But thar be some good news! With a little bit o' tape, you can use t' retainers with 18mm single-use motors too. This video will show you how t' add t' tape in t' right spot so that you can use single-use motors with t' 18mm engine retainers.