Spectral Lamp, Helium, new style with octal (8 pin) base, 30x140mm DxL. Only 4 pins out of the possible 8 pins are used. External starter is not required. Tube suits either the old Spectral Lamp Holder HL3796-101 or the new Spectral Lamp Power Supply with integral tube HL3794-101.

NOTE: Sodium spectral lamp illustrated.