Klein bottle enthusiast Cliff Stoll shows us his unique system for sending bottles to customers. More links & stuff in full description below ↓↓↓ Cliff's online store: www.kleinbottle.com More videos on our Klein Bottle playlist: bit.ly/KleinBottles Cliff Stoll playlist: bit.ly/Cliff_Videos Podcast with Cliff: youtu.be/lxdcBD4ppF0 Numberphile is supported by the Simons Laufer Mathematical Sciences Institute (formerly MSRI): bit.ly/MSRINumberphile We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science. www.simonsfoundation.org/outreach/science-sandbox/ And support from The Akamai Foundation - dedicated to encouraging the next generation of technology innovators and equitable access to STEM education - www.akamai.com/company/corporate-responsibility/akamai-foundation NUMBERPHILE Website: www.numberphile.com/ Numberphile on Facebook: www.facebook.com/numberphile Numberphile tweets: twitter.com/numberphile Subscribe: bit.ly/Numberphile_Sub Videos by Brady Haran Patreon: www.patreon.com/numberphile Numberphile T-Shirts and Merch: teespring.com/stores/numberphile Brady's videos subreddit: www.reddit.com/r/BradyHaran/ Brady's latest videos across all channels: www.bradyharanblog.com/ Sign up for (occasional) emails: eepurl.com/YdjL9