Smeg A1.1K - Manual (Page 8)

Instructions for the installer
42
2.3 Connecting to natural and LPG gas
(Please see connection diagram)
Make the connection to the appliance using flexible
bayonet style hose in accordance to B.S. 669. The
hose connection at the rear of the appliance has a ½”
BSP internal thread. Please use seal C between the
flexible connection L and the appliance supply tube B.
When making the connection, make sure that no stress
of any kind is applied to the cooker and that the hose
does not touch any sharp edges.
If connecting to LPG the bayonet hose must have
red bands on it.