Good quality sealed cartridge bearing bottom brackets to keep your cranks cranking. Square taper, like the good old days. Your basic "cheap + best" simple but mechanically solid solution. Nothing sexy. Nothing more required. Just works. Remember when installing these on old caged bearing bottom brackets that a little grinding might be required to make room for it when adding this to an old bike. Available in a wide variety of spindle lengths, the most common on a Dutch being 127.5mm.