Blackmer's STX2A Transport Pump.
Blackmer's STX2A Transport Pump.

The STX2A pump is similar to the STX3 and STX1220A units but has lower flow rates, operating from 15 to 60 GPM (60 to 227 L/min).
 
It has push rods allowing for slower pump speeds from 350 to 780 RPM, maximum viscosities of 4,600 SSU (970 cSt), dimensional interchangeability with Blackmer TXD2, TXD1220 and STX1220A pump models, weld flanges, chrome oxide-coated stainless-steel heads, PTFE chemical mechanical seals and an internal adjustable relief valve.