ROY RHODES ANGLE PORTING TURKEY CHOKE FOR 12 GAUGE INVECTOR PLUS??

[SKFOOTER]

Does anyone know what the constriction size is for this choke???

[SKFOOTER]

I called Ballistic Specialties in Bates, Arkansas who manufactured this choke and was told it is a .655 constriction.  So I bought it for less than $30 and plan on patterning some Federal HW #7's thru it.    Has anyone tried this choke??