Ditto Yogiboy
60/40 but old stock led/tin rosin core, Savbit was my pick as it also had copper in it to preserve the solder iron tip.
I don't know OS but in Australia you need to find old stock of this, as it's not ROHS approved, and the new stuff they've sub the led for something else and it's nowhere near as good.
[url]http://www.ebay.com/itm/Multicore-solder-size-WK618-1-2mm-500g-ersin-savbit-60-40-alloy-1-2kg-/251996772964?pt=LH_DefaultDomain_3&hash=item3aac2d9a64[/url]
Cheers George