Kirby has talked about these for awhile and I finally found some time to snap some photos and post them sorry it took so long. From left to right: 1.000" 4 port brake for barrels from 1" to .700", 22 cal thru 375. The 1" brake can also be turned to fit flush down to .900". Next is a .875" brake 3 port a slight taper and fits a Sendero barrel perfect, it will work from 22-375 cal muzzle diameters from .875 to .700". The last is the sporter brake .750" 22-338 cal muzzle diameters from .750" to .575". All brakes in stainless are machined from 416 stainless bar stock to better match the color of the barrel, they are not cast and machined like most others. All are available in chromemoly steel as well. There is no porting on TDC or BDC for obvious reasons. The brakes are tunable to the individual rifle and shooter when installed. These brake are in blank form and require indexing, thru hole reamed for clearance, and turned or tapered to fit the barrel. Most contured brakes require these operations anyway these fit a wider varity of barrels in blank form.
Here is a side by side of a blank and a profiled and fitted 1.000" brake, slight taper to fit .900" barrel, thru hole reamed to .295" for a 6.5 STW.