CoolLED has introduced the pE-2 collimator configuration for the precisExcite fluorescence excitation system for microscopy. The collimator is suitable for live-cell imaging and fast-switching (~300 μs) applications. Offering greater flexibility, it incorporates high-performance optics that are interchangeable. Available multibandpass filter sets, which can be used in conjunction with the collimator, fit in the microscope’s filter cube to allow high-speed switching with no moving parts. Excitation filters also can be fitted inside the collimator.