trevorr
Member
I'm 99% certain that it's a Sta-Lok Turnbuckle. Well atleast the other one in view is, as you can see the orange dot on it.A couple of friends indeed had to use an angle grinder to cut the turnbuckles, and after having tried all sorts of potions, heat, etc.
I use Lanocote when first mounting them. it works very well they can be screwed or unscrewed even several years later.
Looking at the picture, they look identical to mine: can you see "ACMO" engraved on the turnbuckle body, or in tangs? If so they are most likely stainless steel. Open cage bronze ones from Selden etc have a slightly different shape.
In which case its a Bronze alloy.