Some stupid Skyway wheel questions.

[jp-rebel]

Sorry if im being really dumb but I would like some help with the following questions ,first off I thought you might like to see my before after pics.







Now does anyone know what the 2 knurled things that are sticking out either side of the freecoasterwheel?(see pic below).
 
Also I  need some  new wheel/track nuts what TPI do I need.And what do the serial numbers pressed into the rims mean,the front has 1494426 and the back has  1491462.
Cheers.

[harris]

is it one of the switchable coaster set ups that releases the coaster to freewheel 26tpi or 24 tpi will be the threads depends which one you have
as the came with either.