Why do fizzy bottle threads have gaps in them?

Ever noticed the small gaps in the thread of a fizzy drinks bottle? They’re designed to let pressure safely vent as you unscrew the cap. They became a news story after Walmart recalled around 850,000 reusable bottles that allegedly lacked this safety feature, with reports that pressurised lids caused serious eye injuries. A tiny bit of bottle design that turns out to be really important. This episode of Recycled Content, is the 'Rubbish Question' from episode 53 of Talking Rubbish, which first aired on 31st July 2025. While every effort has been made to provide the most accurate information, recycling guidance changes quickly and some advice may become outdated over time. Always check with your local council for the rules that apply to recycling in your area. On the main Talking Rubbish podcast, we include an additions and corrections section where we update anything we may have got wrong.These clips come from the weekly show, Talking Rubbish - The Recycling PodcastWe would love you to join our community on DiscordSpecial thanks to our sponsor, EcosuretyTo get exclusive videos and clips, follow us on Instagram, TikTok, X, Threads or Facebook; @rubbishpodcast or YouTube: @talkingrubbishpodcastOr you can contact James and Robbie with questions or just general rubbish musings using the email address [email protected] or by texting them via WhatsApp on 07356 069 232Music licence ID: 3GXXBILNPGLYRUZF