This item is a for a small Pilot Bulb holder, with a rubber surround. These are from a small batch of 'New Old Stock' holders I have had for many years.
Price is each (note: bulbs are sold seperately)
Not sure what they were originally to fit - but the bulb surround is rubber and looks like it may have originally been made to be pressed into an old style headlight reflector pilot bulb hole, idiot light binnacle or similar (you can see a small recess in the rubber surround, where it may have pushed into), but may also be possible to push the rubber into a similar recess on an old motorcycle panel or speedo bulb receptor. The outer diameter of the rubber surround is - 17mm, with the rubber recess being approx 13mm diameter - i.e. it could be pressed into a hole of approximately 13mm or slightly larger - such as an old headlamp reflector as a pilot bulb holder.
I have had these for many years, but thought worth listing at the same time as listing the Lucas pilot bulbs shown here - as not always easy to find holders.
As these are 'old stock', the connectors look slighty tarnished - I would advise rubbing them and the central bulb connector with a bit of emery paper before fitting the builb.
However, these have the correct bayonet fitting for the Pilot/Instrument bulbs shown in this section - i.e. to fit Items 1161/1162 (but not Item 1163 which has a different type of bayonet)
for detail Price is Each