The Robo style screw cap, aKa National DP Cap is a short skirt and a short turn to seal the septa against the vial. The short skirt will allow older style robotic autosamplers to pick up the vial and cap by placing a fork like device under the cap and lifting it from its tray, into the autosampler position. This was very important for Agilent 7673A autosamplers which are not sold any longer but there is still a large installed base in the market place.
When our Soft-Guard™ and other more traditional screw caps were designed, they were designed to fit the criteria of the Robo style cap discussed above and work in the Agilent 7673A the same. However one of the features that were not popular is that the “Robo Style” cap is smooth and they slip under your fingers when tightening them. Especially when tightening 100 or so caps. The knurled skirt of the Soft-Guard Caps makes it easier to grip the cap for tighter fits on the vials.
Click HERE for to view our most popular Robo Style Cap.