https://stream.echo6.co/videos/watch/cadac1a9-1f2d-4ddd-a5b3-1ae1e5ba3b7d A very odd little thing. I initially thought that this was based on a magnetic latching system, but it turns out that it uses a length of a special wire that contracts significantly as it heats up. It means that this unit is very simple with a minimum of mechanical parts and is not influenced by a string external magnetic field as some magnetic units are. The wire is theoretically rated for millions of cycles with this small controlled movement. Although rated for a higher voltage, I tested this with 1V to slow down the actuator movement. The electrical data at 1V is: Cold resistance 2.86 ohms (350mA at 1V). Hot resistance 2.5 ohms (400mA at 1V). The unit is normally rated for 3 to 5V. The unit only energises the wire for the length of time it takes to release the catch, as there is a switch inline with the muscle wire. As with many items I've been buying recently, this one came from AliExpress (not a sponsor) Here's a non affiliate link to the listing. https://www.aliexpress.com/item/1005005211494161.html The cost should be around £2.50, and it may appear as a bundle deal item. If you enjoy my videos, supporting the channel on Patreon helps keep it independent of YouTube's quirks, avoids intrusive mid-video adverts, gives early access, bonus footage and regular quiet Patreon live streams. https://www.patreon.com/bigclive Alternatively, for a single coffee contribution you can use PayPal:- https://www.paypal.com/paypalme/bigclive #ElectronicsCreators Wed, 10 Jun 2026 07:03:48 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/cadac1a9-1f2d-4ddd-a5b3-1ae1e5ba3b7d All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.