> For the complete documentation index, see [llms.txt](https://hrftank.gitbook.io/hrftank/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hrftank.gitbook.io/hrftank/ii-build-manual-hull-and-chassis/3.-drive/3.2-parts-required-for-this-step.md).

# 3.2 Parts required for this step

* Bearings:
  * LM4UU bearing (8 pcs)
  * 696 bearing (24 pcs)
  * 623 bearing (12 pcs)
* 4 x 100 mm linear rail (4 pcs)
* 2 x 70 mm steel rod (250 pcs)
* 15 mm x 60 mm spring, 1.2 mm wire (2 pcs)
* [Pololu 2674](https://www.pololu.com/product/2674) wheel adapter for 6mm shaft

{% hint style="warning" %}
All screws are socket head cap screws, unless otherwise stated.
{% endhint %}

* Screws and nuts:
  * M3x10 screw (10 pcs)
  * M3x14 screw (2 pcs)
  * M3x60 screw (at least 14 mm of thread, preferably **full thread** - 6 pcs)
  * M6x80 screw (full thread, button head - 2 pcs)
  * M6x65 (Phillips pan head screw - 2 pcs)
  * M3 self-locking nut (8 pcs)
  * M6 self-locking nut (4 pcs)
  * [*2x6 mm self-tapping screw (500 pcs)*](#user-content-fn-1)[^1]
* Heat-set inserts:
  * M6x8 (OD 9 mm, 2 pcs)  

### Track link press (optional)

* *M6x8 (OD 9 mm, 1 pcs)*
* *1.5 - 1.7 mm steel rod (eg. 1.7 mm metal drill bit)*
* *M6x95 **full thread** screw, hex countersunk/socket head*

[^1]: for rubber track pads attachment