> 3/32" - most places don't sell those plugs ( Radio Shack does not ) WHAT!??!! radio shack DOES TOO have those i got one there for $3.00 and it goes from headphone size to link port size, you plug the adap. onto your headphones and the other(male) end into the bottom of the calc. Andy Haninger aka &y ahaning@freenet.columbus.oh.us