A closed-loop fluid transfer system comprising: a first valve assembly adapted to be mounted on a first container; a second receiving valve assembly adapted to be mounted on a second container; a measuring adapter having a first end and a second end, and a chamber located between the first and second ends configured to hold a volume of fluid; wherein the measuring adapter includes a first receiving valve assembly located at the first end of the measuring adapter, said first receiving valve assembly being configured to engage and actuate the first valve assembly, wherein the first receiving valve assembly includes a receiving valve member; wherein at least a portion of the receiving valve member of the first receiving valve assembly is separable from a portion of the first receiving valve assembly on the measuring adapter to create an opening that provides fluid communication to the chamber when a linear force generated by a rotation of the first valve assembly is exerted on the receiving valve member of the first receiving valve assembly of the measuring adapter; wherein the measuring adapter includes a second valve assembly located at the second end of the measuring adapter, said second valve assembly being configured to couple to the second receiving valve assembly, wherein the second valve assembly includes a valve member; wherein at least a portion of the valve member of the second valve assembly located at the second end of the measuring adapter is, by rotation of the second valve assembly, separable from a portion of the second valve assembly to create an opening that provides fluid communication out of the chamber. a first valve assembly adapted to be mounted on a first container; a second receiving valve assembly adapted to be mounted on a second container; a measuring adapter having a first end and a second end, and a chamber located between the first and second ends configured to hold a volume of fluid; wherein the measuring adapter includes a first receiving valve assembly located at the first end of the measuring adapter, said first receiving valve assembly being configured to engage and actuate the first valve assembly, wherein the first receiving valve assembly includes a receiving valve member; wherein at least a portion of the receiving valve member of the first receiving valve assembly is separable from a portion of the first receiving valve assembly on the measuring adapter to create an opening that provides fluid communication to the chamber when a linear force generated by a rotation of the first valve assembly is exerted on the receiving valve member of the first receiving valve assembly of the measuring adapter; wherein the measuring adapter includes a second valve assembly located at the second end of the measuring adapter, said second valve assembly being configured to couple to the second receiving valve assembly, wherein the second valve assembly includes a valve member; wherein at least a portion of the valve member of the second valve assembly located at the second end of the measuring adapter is, by rotation of the second valve assembly, separable from a portion of the second valve assembly to create an opening that provides fluid communication out of the chamber.