SQ: Special Quality Lab Reagents

ExcelaR: Excellent Analytical Reagents

The former (SQ) is less pure (and more economic)  than the latter, so I think that SQ can be considered as AR grade

Thanks a lot, Mr. Polesello.

You should ask the company to provide specs

As I understand, the Excelar is equal to AR (analytical reagent ) grade.AR grade is of pure  quality and costly.AR grade is used for preparation of standards etc.

Yes, ExcelaR is equivalent to analytical grade reagent (AR).

''ER'' grade of Qualigens is equivalent to the ''AR (analytical reagent)'' grade, and ''SQ'' grade of Qualigens is equivalent to the ''LR (laboratory reagent)'' grade.

Thanks to all