Originally Posted by toddimusnimski

I copied this from elsewhere:

RECALL: Smith & Wesson has shipped over 300,000 Third generation Pistols. We have had a very small number or reports where a dropped pistol resulted in a broken grip resulting in a failure to fire by releasing mainspring tension. Resultant testing and review have shown that a pistol dropped at a specific angle can cause a fracture of the grip.

As a result of these occurrences and our testing, we have made a change in the grip material to a thermoplastic alloy of increased durability. This new material, which is now being used on all current production models, can be identified by a dimple on the bottom of the grip, next to the large opening. Additionally, the blue product box has a green dot sticker on the label end.

We believe it unlikely that you will experience any problem with your original grips. However, in order to safeguard our customers from the possibility of such a malfunction, we will make available, free of charge, an easily installed replacement grip. Please inspect your pistol and if you have a model listed below that does not have a small dimple next to the large opening, please write us including your model and serial number or call 1-800-331-0852. If you prefer, you can send your pistol to a Smith & Wesson Warranty Station where we will replace the grip for you.

Models Affected:

3904, 3906, 3913, 3913LS, 3914, 3914LS, 1006, 1066, 4506, 4516, 4516-1, 5903, 5904, 5906, 5946, 6904, 6906 & 6946

Smith & Wesson's development process is a continuing one. We are constantly striving both to develop new products and improve existing products. We are committed to building the safest, most reliable, finest performing firearms possible.

When I see the occasional 5900 series grips for sale at the local show I check the bottom. More often than not there is no dimple so I pass on them. Those older grips I've seen also seem to have more of a dark grey appearance