Uh, it is the original ry4 manufacturer. Hangsen created the original ry4. 
3.3% should be good to start. 4% should be sufficient.
All the other ry4s people like out there are heavier and sweeter I think, than the original.
3.3% should be good to start. 4% should be sufficient.
All the other ry4s people like out there are heavier and sweeter I think, than the original.