The highest quality black E27 bulb holders, base has m10 metal thread commonly used for small lamp fittings and ceiling pendant lamps.

There are many cheaper variants of this type of bulb holder and many crack or don't screw together properly as the quality and tolerances are very poor. I sourced these much higher quality bulb holder to use for my own lamp business as I was breaking the cheap one I sourced on ebay from other sellers.

This is UK stock, dispatched next day with Royal Mail 2nd class or Hermes 2-3 day