# Elements of the Order Book

**Working volume**   

This option maes it possible an adequate working volume selection. It displays the lot size and leverage size when closed. When the window opens it shows:

* Balance 
* Choice of calculation as a percentage of the base or quotation currency 
* Lot size Minimum available volume 
* Maximum available volume for purchase 
* Maximum available volume for sale

  <figure><img src="/files/4xk6bwphROEG9tfMn6FD" alt=""><figcaption></figcaption></figure>

**Price multipliers**&#x20;

A numerical multiplier allows you to change the visible range of prices in the Order Book (a close analogy is the scale on a map). For example, with a multiplier of 1, the price step in the order book is equal to the instrument step. And with a multiplier of 10, the price step increases 10 times and allows user to see an increased price range. It is possible to select a multiplier value from those proposed or add your own in a separate input field.

<figure><img src="/files/JjnWqdLOdCyP2DPPLriu" alt=""><figcaption></figcaption></figure>

#### Midline

Midpoint is a conditional line dividing at the center the spread and the Order Book itself. It serves as an additional visual indicator for a quick determination of the DOM center.

<figure><img src="/files/dNYTGNX0nI8LhEgnqTTb" alt=""><figcaption></figcaption></figure>

**Highlighting round price levels**

A round level is a price level that is a multiple of the set value. Recall that the set value represents a price step.

For example, one can set the level equal to 10. In this case, values ​​that are multiples of 10 should be highlighted and the rest left as normal. That is, the values ​​70.30, 70.20, 70.10, 18853.0 will be underline.

<figure><img src="/files/BwyA6GYaKTw00dqx2aUv" alt=""><figcaption></figcaption></figure>

**Double filling scale for price levels**

The double scale indicator displays the dynamics of changes in the volumes of the traded financial instrument at each price level. The corresponding visualization appears in the form of some double histograms. Each of these histograms shows the intensity of movement of limit orders at levels and the strength of the levels themselves. The double scale is displayed only on the Order Book volume scale.

<figure><img src="/files/C7wKTuqTKaaMsLWdqQLs" alt=""><figcaption></figcaption></figure>


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