Connect your headset with an RJ plug to your handset with 2.5mm, 3.5mm plug or to your PC with 2 x 3.5mm plugs with one of these adapters.
BT200 - 2.5mm jackSPA941 - 2.mm jackGXP2000 - 3.5mm jacksnom & Polycom handsets - RJ connectorPC - 2 x 3.5mm