I recently bought a Kim pickup sail - for recovering MOBs from the drink in a horizontal position. You attach the bottom of the sail round a pair of stanchions with straps which have a seatbelt-type buckle, attach a halyard to the top of the sail and roll the casualty up the side of the boat. When we tested it on SWMBO in East Cowes Marina (off a pontoon) the straps parted and she fell down the side of the boat into the Medina (easily recovered by me, but she wasn't pleased!). We had followed the instructions (such as they were).
After that we tried everything we could think of but couldn't get the straps to hold fast. Today we took the pickup sail back whence we bought it (Force 4 in Bursledon) where the staff member quickly diagnosed an assembly fault - the strap was incorrectly led through the various parts of the buckle. He had to prise the cover off with a screwdriver to fix it, which he did, and we tested it this afternoon with me as the casualty - no problem. I am posting this to warn anyone who has bought this safety item and not tested it to check it out now (not when you have a real MOB situation). We know that it wasn't just our pickup sail that was wrongly assembled, because when we were in Lymington at Easter we had a close look at another one on sale in a chandler, and that one wouldn't have worked either.