You can use this height-adjustable saddle to achieve different afterlength-to-bridge string angles. Why would you do that? The height of the saddle can affect several things on your bass; your instrument's tone, the hard or soft "feel" of your strings under the hands, the propensity of the bass to have wolf tones, and more. The string angle, in conjunction with the string tension, determines the pressure that the bridge feet exert on the top. This is often decisive for the tonal development of an instrument. Saddle height is an oft-overlooked means for making subtle (or not-so-subtle) changes in an instrument's setup and tone.
The ability to change that height is also a useful feature; since different types of strings or brands require different string tension, there can be significant fluctuations in the load on the top. Once installed, the height-adjustable saddle enables the string angle to be easily adjusted to the optimal conditions for the respective instrument.
The saddle is designed in such a way that a change in the saddle height does not affect the length of the hanging string. Neither gluing nor screwing is necessary for assembly.
As you can see, the string angle is changed by inserting the movable rounded "saddle" into the different heights of the milled holes in the main unit. The Tailpiece cable, passed over the rod, changes the string angle with the tailpiece connected to it, by simply raising or lowering the height of the saddle at your option. Three different heights are available, and it takes only minutes to switch between them.
Professional installation recommended (the old saddle must be removed, and you will likely need to widen the opening in the bass lower edge.)