I want to use my Akto without Inner and make polycro or tyrek groundsheet. I just seen this on ebay: https://www.ebay.co.uk/itm/Tyvek-fu...455181?hash=item41db14ea0d:g:xCsAAOSwHMJYHdtH I dont mind paying extra for someone to do it for me. However I am thinking having this ebay set up might be just as effective as only having a piece of tyrek sheet underneath me without the attachments? cutting a bit of tyrek into shape and just bang it underneath me. I dont see what the big difference is? Ideally I would make a bathtub but no idea how. Thank you.