Adjustable volume models allow 5 of the laboratorys most frequently used volumes to be set up and stored for routine use and later recall. Other volume settings can be selected at precise increments throughout the pipettes range. A low-force, form-fitting plunger manually controls aspiration and dispensing speeds with minimal effort. This is especially important for samples containing cells with fragile membranes that can be easily disrupted, or fluids that tend to bubble.