(From company literature) SLIK SBH-550 Professional Ball Head. SLIK's new professional ball heads are made with exceptionally fine machining and carefully anodizing of hardened aluminum parts that are designed to give many years of trouble-free super smooth operation. These SLIK ball heads feature an easy to use, single knob operation to lock or release the ball connected to the camera plate. The knob is oversized and has a well-textured surface for a sure grip in any conditions.
When the head is released, not only does the ball portion of the head move freely, the main body encasing the head can turn on its base for quick and easy movement as well. The base of the head has easy-to-read degree markings for panoramic photography.
The SBH-280 is capable of handling a digital SLR or 35 mm film cameras. The SBH-320 is recommended for medium format cameras and can be used with digital backs or telephoto lenses. The SBH-550 can handle long telephoto lenses and 4x5 field or view cameras.