|L33: CONCRETE FENCE POSTS (12)|
3 bar fence needs 0.7mm wire. 12 per pack.
While not aware of any standard spacing for such posts, if they are set 34mm apart (2.6 metres or 8ft 6 in) 12 posts will give a scale run of about 31 metres or 100 ft.
(OO Gauge / 4mm Scale)