The invention provides an improvement in a slip ring (20) adapted to provide electrical contact between a stator (21) and a rotor (22). The improvement includes: a current-carrying conductor (23) mounted on the stator; a brush tube (24) mounted on the conductor; a fiber bundle composed of a number of individual fibers (26), the upper marginal end portions of the fibers being received in said brush tube, a portion of the brush tube being crimped or swaged to hold the upper marginal end portions of said fibers therein, the lower ends of the fibers in the bundle extending beyond said brush tube and being adapted to engage said rotor; a collimator tube (25) surrounding a portion of the brush tube and extending therebeyond, the lower end of the collimator tube being adapted to limit lateral movement of the lower marginal end portions of said fibers in said bundle when the rotor rotates relative to said stator; and a fluid reservoir mounted on the collimator tube (28). The fluid may be an lubricant, a corrosion inhibitor, a fluid having a high dielectric strength additive to prevent arcing, or some other fluid.