Epi Tube Holder/adapter for fluorometer cuvette

This adapter holds a 0.5 ml centrifuge tube in position for reading by the Promega Quantifluor ST. The instrument manufacturer makes an adapter for 0.2 ml PCR tubes, but not the equivalent for 0.5 ml tubes. Additionally, the adapter from Promega costs several huundred dollars; this is considerably cheaper. Effectively, this is a cuvette-shaped tube holder for fitting a tube into a fluorometer but the Z-height may not work for any but the Promega Quantifluor ST. Minimum volume is ~50 ul.