Just had a mad scientist moment and made something similar out of some old safety glasses out of me van.
I used a paint brush & paint to mark on them roughly where my eye would be when in stance and aiming, got a 0.8 drill bit out of me model making kit and drilled a hole, then sprayed shooting eye side black and blind side white.
Seems to work quite well, and does bring everything into sharper focus, even the point of aim is crisper.... its done nothing for my groups, but thats just me struggling with non fitting grips
I might well pursue this eyedea.......see what I did there(?) ..... and there ....
Thanks again to everyone
ATB Sean
Slowly morphing into an RWS/Diana/Original fanboy.
Definitely a springer fanboy.