STYROS® 2R Simulated-Monolith™ Polymeric Reversed Phase. Separation of 5 peptides on Narrow Bore column of 2.1 mm ID. Acidic and Basic pH’s STYROS® 2R Simulated-Monolith™ Polymeric Reversed Phase. Separation of 5 peptides on Narrow Bore column of 2.1 mm ID. Acidic and Basic pH's