sigma off the bourse, page-11

General accounts for daily orders are 30 days, some special deals you might get 90 days forward charge max. It has been going on as regular practice for years and all wholesalers do it. The forward charge deals are usually facilitated through the manufacturer and Sigma will also have extended credit terms themselves with them.

It is pretty competetive out there but with only 3 main players in the game I don't think Sigma would have to overdo the extension of credit.