I've tried numerous fly papers over the years, top brands and cheap ones. These are far the best. Easy to undo, like a film catridge, no getting to the last bit and having the paper rip and getting it stuck to your hands (and hair). My only qualm is that when the wind gets up, the paper part with the hole isn't strong enough and rips....leaving a sticky mess wherever the paper has landed on my terrace. I must add that I use these in Spain and they are invaluable as we live in a rural location with mega flying critters!
From the photos you can see the difference..no flies on the brown paper, that hasn't even unravelled (38C) and the others are loaded with flies. Ihave put gaffer tape on the end to strengthen the hole where it attaches to a hook I have in the ceiling.
infinitely better than the old brown paper variety. The sticky strip is in a cartridge (like an old roll of film), so slides out easily. Pretty pattern of flowers on it don't necessarily attract the flies but it definitely looks better than a brown bit of paper. No smell, very sticky and stays sticky. Make sure you place it out of a draft... the flies don't seem to land on it if its waving about!
It has been hanging for over a week does not seem to attract any flys four so far but plenty still flying about the flat only seems to work if one flys into it .