The SE300 B is the pre-amp for the Blue Line Series capsules CK91, CK92, CK93, CK94 and CK98. This system is designed for excellent audio quality and maximum flexibility. Its robust Modulock? bayonet coupling allows quick and easy changing of the capsules. The state-of-the-art electronics design ensures high RF immunity in critical environments. The SE300 B provides a switchable bass roll-off/attenuator with three positions: flat, 75Hz and 10db attenuation.