Simple and easy to install. Adds extra leverage for manipulation of the bolt. Its also quite a bit more ergonomic then the original. Comes in several colors.
I first came across something like this while working on a Rem 700 bolt and at first was going to make an aluminum one but I thought with the cost it did not seem like it was competitive enough. Enter the plastic version. It is streamlined and simple to install. Has two alignment pins that snap it together. Uses a Philips head bolt to tighten up and comes with E6000 glue. Without the glue I do not think this product would have ever worked. The nature of the round Bolt knob would have let it spin too easy, but the glue is the perfect consistency. It is not permanent and can be removed easy yet is firm enough to holt it in place.
I highly recommend that you check your bolt knob to make sure it is the same kind. Savage previously made a machines one that had a thinner neck and though it might work I think fitting will not be optimal. In the future I will try to make one that will fit the older style. Check the photos with he calipers and check the size of yours to make sure it fits. Back should be 0.300 give or take 0.010-+ and the ball knob itself around 0.800 once again give or take 0.010-+