JAG Hook Sharpening Stones JAG Hook Sharpening Stones. An ULTRA sharp hook is one of the biggest edges in modern specimen angling. It takes practice to sharpen hooks to perfection, but the biggest hurdle anglers face is inadequate tools for the job. This is why JAG Products have developed the SP (surgical point) Stones in 2 different grades. Used in conjunction with JAGs Ultra Eye, hook points can be sharpened to a level far superior to ANY hook straight from the pack.Medium grade. Ideal abrasive for general sharpening. Fine grade. Perfect abrasive for smaller hooks or final honing.