this drop tube loading arm assembly is adaptable for loading asphalt into tank trailers at marketing terminals . the telescoping drop tube employs guides made of steel rollers of polymers such as fluorocarbon polymers and aluminum . the guides are located in the annular space between the tubes in combination with increased radial clearance between the tubes or sleeves and in combination with protection for the overfill probe . with the addition of vapor control systems and overfill protection probes , the telescoping drop loading spouts are less susceptible to cold weather sticking problems .