The L-tronics preamps are 32 channel preamps with 10x gain 32ChanAmp1_Aug1_Final.pdf.
They are based around the INA121 Burr-Brown amplifier ina121-1.pdf.
The connectors on the preamp board are Digikey part number 151240-8422-tb.
The mating connectors on the shielded cables are Digikey part number 150240-6002-rb.