They were a cheap early Bridgestone. They were light, later ones were better, a little. I was around then, roaming the earth's surface on a bike, S. Brown & others have had their view of them. For Me and friends, they were good bikes to have around and ride while the glue on the sew-ups on our Raleighs dried.
The '75 .. 77 models with the Al. bonded lugged frame cost around hundred +