T' 18mm Engine Retainers were designed t' be used with t' Aerotech 18mm reloadable rocket engines, me bucko, nay t' standard single-use motors (from Estes, Quest, shiver me timbers, Apogee, or Aerotech). Ahoy! But thar be some good news! With a little bit o' tape, you can use t' retainers with 18mm single-use motors too. Begad! 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.