C4 Front Sight Post
Replacement aperture for all C4 Front Sights, available in many sizes for your specific application.  
C4 Rear Aperture
Replacement aperture for C4 Rear Sight.
Sight Adjustment Tool
Use the Ultradyne Sight Adjustment tool for easy replacement of rear sight apertures or to adjust elevation of A2-style front sight posts.  
Oversize Shrouded Timing Nut
Installation of Ultradyne Muzzle devices on heavy barrels requires a larger timing nut. Use this timing nut for those barrels up to 1 inch in diameter.
Muzzle Device Collar
Replacement collar for muzzle devices without a Dynamount accessory such as the C4 Dynamount Front Sight mounted.