Flat Base & 150mm ball
The BL-150 ball base adapter is included inside the kit, which converts the flat base head into a 150mm ball head.

Importance of counterbalance
When looking for a suitable tripod head for your camera, one of the most important aspects to consider is counterbalancing capability. The counterbalancing function provides a counterforce to keep the balance between the tripod head and the camera that is mounted on it. If the right counterbalance is maintained, the camera remains stationary at any angle of tilt. You do not need to worry about holding the camera by hand and yet are able to maintain precise control of the camera.

Counterbalancing capability
RS/RS PLUS/QD is equipped with an excellent counterbalancing system that provides a perfect counterforce that corresponds to the weight and angle of the camera. A special innerspring mechanism is used for this system. When the strength of a spring is insufficient, the head cannot bear the weight of the camera. If a spring is too strong, the camera will tilt upward. RS/RS PLUS/QD "variable counterbalance system" enables users to adjust the strength of the innerspring within a certain range using the counterbalance knob located on the outside of the head. Different cameras can be used and a perfect counterbalance can be set for each individual camera.

Counterbalance chart to help you choose the perfect tripod head
The definitive way to find the most accurate counterbalance between camera/accessories and a tripod head is to actually mount the camera on the head. However, you can use this counterbalance chart to get a rough idea of the correct counterbalance. The vertical axis of the chart depicts the height of the gravitational center and the horizontal axis is load weight (total weight of the camera and accessories). Based on the combination of these two elements, you can find a suitable tripod head for your camera. The area between the two curved lines represents the range of counterbalance that you can set with the counterbalance adjustment knob. When a standard lens, microphone and battery are used, the normal height of the gravitational center is approximately 200mm/7.9"(box lens), 125mm/4.9"(shoulder type camera) and 75mm/3"(hand-held camera) The height of the gravitational center will not shift much even when a different lens or a different battery is used on the back of the camera. Please be aware that attaching a light or a monitor on top of the camera will shift the center of gravity.

Counterbalance range 15 to 35kg / 33.0 to 77.0lb (C.G.125mm)
Payload 40kg / 88.0lb
Counterbalance Continuous
Drag mode 7STEP
Tilt angle +90° / -70°
Weight 21.4kg / 47.1lb
Height 97.5 to 186cm / 38.5 to 73"
Ball diameter 150mm
Section 2STAGE