"The" Universal R Matrix in Quantum Groups

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For a quantum group (a quasitriangular Hopf algebra) $A$, it has a distinguished element in $A \otimes A$ called the universal R matrix in many texts (e.g. Kassel). This confuses me, because nowhere do I see any statement about uniqueness of $R$.

In my brief reading, it does not seem that $R$ is universal in the categorical sense, nor is it unique. This element just seems to generate R-matrices via representations over modules. Is this the sense in which "universal" is used?

To summarize my question, in what sense is $R$ universal, and in what sense is it unique? Is it really appropriate to call it the universal R matrix?