BCY are the main makers of archery string material and Halo is their flagship all-round serving thread. It is braided to increase wear resistance, strong for tight servings and comes in a wonderful variety of colours. 

It is a well-known "fact" that good looking bows and strings shoot better. ;) 

We recommend getting the best from the start for this product. String serving coming loose will make it next to impossible to shoot well and may ruin your weekend. This spool will last a LONG time. 

Finally, it is recommended when tying on nocking points to use the same size serving thread to lock into the serving rather than sliding between or over the top. 

NOTE: Images show the colours, but not the spool type (which is shown in the original image).