They are .002" oversized on the OD (less than the thickness of a sheet of paper). Because they are not compatible with Volquartsen pistols OR uppers, they are discounted .
These bolts will work with Ruger pistols, whether they are MKII, MKIII (the loaded chamber indicator must be removed on the MKIII models), or MKIV, including LITE models.
This is a great opportunity to upgrade your Ruger pistol for less!