INTLLAB Magnetic Stirrer Stainless Steel Magnetic Mixer with stir bar (No Heating) Max Stirring Capacity: 3000ml: Amazon.com: Industrial & Scientific
INTLLAB Magnetic Stirrer Stainless Steel Magnetic Mixer with stir bar (No Heating) Max Stirring Capacity: 3000ml: Amazon.com: Industrial & Scientific
www.amazon.com
Thats the one I use - I use it for more than just normal testing vials (a 500 ml erlenmeyer for alk calibration for instance) so I wanted one I could use any vessel on.
I also use it to mix DIY All-for-Reef in 1 a liter flask.
I wanted something I could plug in as well rather than battery operated.
I made a DIY one using a computer fan, hard drive magnets and a 3d printed case - it worked OK - once I started using it a little more I decided to buy one.