sr555SR555 Current Preamplifier. 10 VµA gain; 120 kHz (-3 dB) bandwidth; SR556 Current Preamplifier. 5 fA√Hz input noise; 1 VnA gain; SR556 Current Preamplifier. 5 fA√Hz inputWe have 1 SRS Labs SR555 manual available for free PDF download: Operation Manual . SRS Labs SR555 Operation Manual (10 pages) Current Preamplifier. Brand: SRS Labs | Category: