Buffered Hypotonic Solution is well known hypotonic solution developed for bone marrow specimens. It has been found to achieve good metaphase swelling (spreading) from a wide range of bone marrow types. It contains 0.4% KCL with HEPES. It significantly increases the number of useful metaphases in leukemic bone marrows when compared to the standard 0.075M KCL hypotonic. Makes 1 litre of reagent