Perhaps we should have a system of notifying each other of potential pyro-related bargains! Maybe threads starting with the word bargain! I've just bought 4, 100mm x 45m rolls of aluminium foil tape at £7.58 each from ToolStation. http://www.toolstation.com/shop/Adhesives Sealants/Tapes/Aluminium Foil Tape 100mm x 50m/d180/sd2420/p53122 vs. Screwfix, who were cheap on this 4/5years ago... now £16.99! And it's particularly nice because it's obviously sticky enough to adhere, but not so strong that it instantly welds to your skin, rips your finger prints off and become generally unmanagable! Found it via mobile google search and ToolStation mobile site showed me stock at nearest branch, the full website doesn't seem to want to show for 100mm width unless you log in. Don't know if anyone else uses it. It might be a hang-over from when I worked professionally. I've partly come to think it's an unnecessary extra expense/fuss, like additional waterproofing in a way. All extra time, effort and money. But then it's an insurance against crossfires, making a display messy and shorter. And it allows me to set up in a small area. Some cakes have a slightly foil-like top to them, but I'm not sure that in itself would prevent a large stray star burning through. But cakes with a layer of thick paper (almost cardboard) on top probably don't need the extra effort. I waterproof my pryo in parcel tape too, which some of you will probably think mental for. It takes an age, but I do it whilst fusing for electrical firing. Would have to make the igniters secure anyway. It saves having to do it all on the day. And I suppose the biggest potential benefit is if the weather was 50/50 and it suddenly heaved it down once the material was set out, I'd be relaxed knowing it was 100% tightly waterproof. However, I do think these additional layers can impede stars from smaller cakes, such as night vision/moving target. Last year I completely replaced the top packaging of some cakes with my foil&waterproof layers.