The Preston Innovations Stotz are a hybrid fishing shot designed for use on larger diameter lines (they also work perfectly on fine diameters too).
The wide groove on this Stot design makes placing them on the line quick and easy. The Preston stotz also boasts an increased surface area that helps to grip the line. This prevents damage and also stops the Stotz from pinging off under stress. The flat ends of Stotz produce a neat bulk when they are grouped together.