That's a Kepplinger set trigger, made in Austria. You can fire the gun with the trigger set or unset, handy in a sporter rifle in cold weather. Unset, the trigger is a crisp three or four pounds... I haven't weighed it. Set the trigger pulls only a few ounces, again very crispy. This is perfect for shooting off a bench when you are being very fussy.

I have had a lifelong battle with Ruger triggers. This is an expensive but really good cure.

Brownells sells Kepplinger triggers.

Dick Wright