One of my variable tension strops. If you are just getting started out - this is probably not the best choice for you, and you might want to consider "growing" into something like this over time. They do hold some key benefits as far as customized utility and comfort go. You can get them with as many interchangeable leather belts as you like for loading with variable abrasives, and you can control the amount of tension on the belt and thus control the amount of "drag".

These can pretty much be made in any width or length, although I would not recommend going overboard with the dimensions of the strop - it simply isn't very comfortable over a certain size. The one in the pictures is about 80 mm X 80 mm X 470 mm (not including the handle) and has it's very own customized tension regulating key