I use Sunlite Ergo grips that lack locking rings which take away space. Also their protrusions are squishy which helps when packing the bike into a tight case such as B&W. The rotation around handlebars can be prevented just by placing a piece of tape onto the handlebar, under the grip. Otherwise, you cut them with a utility knife to desired length.
Amazon product ASIN B0013G8OSUView: https://www.amazon.co.uk/Sunlite-Ergo-Ridge-Mountain-Bicycle/dp/B0013G8OSU/
Amazon product ASIN B0013G8OSUView: https://www.amazon.co.uk/Sunlite-Ergo-Ridge-Mountain-Bicycle/dp/B0013G8OSU/