Roger:
While grinding dog is the more popular term for these two lug dogs, I have to agree
with Peter S., I have always called them carriers. I prefer this style of dog instead of
the straight or bent tail single lug dog. The double lug carrier has one major advantage
over the single lug type, the ability to remove all backlash between the driving pin and
the carrier. Even if the pin is smaller than the narrowest space between the lugs, a
snug fitting bushing fitted to the pin solves the problem. The pin can be nicely slid down
into the "V", making perfect contact. When properly adjusted, there is no stain on the
center or any backlash. I use this type of carrier for all of my gear cutting and grinding
work were any lost motion could cause problems. They are also very handy for turning
between centers in a lathe.
Hendeyman