In 2mm glass. It would have originated from a BR fogmans lamp & 4 are needed to complete one aspect of a three aspect lamp OR 3 needed for a 4 aspect lamp.
Antique British Railway Hand Lamp – Welch Patent – Lamp Mfg London
BRITISH RAILWAY HAND LAMP GLASS 4.00 IN DIA 3MM THICK BEVELLED EDGE VGC
BRITISH RAILWAY HAND LAMP RESERVOIR 77MM DIA & BURNER - 20 MM SLIDE FIXING SHAFT
ONE BRITISH RAILWAY HAND LAMP CLEAR GLASS SEGMENT C 1950 BR 12cm x 2.2cm 4 AVAIL
ONE BRITISH RAILWAY HAND LAMP BLUE GLASS SLAT C 1950 BR 12cm x 2.2cm 4 AVAIL
British Railway Hand Lamp Glass 100mmDIA 3mm Thick Bevelled Edge
