National 400 Instructions Manual page 2

405TBL series has 45° inclined head
Head of microscope
Objective lens
Incidental (top) illumination
(included on all models except #400)
Power switch
Stage clips
Stage plate
Base
(Illustrated is #400TBL
having both incidental
(top) and transmitted
(bottom) illumination)
Plain base on non-illuminated #400
Eyepieces (ocular lens)
Base on top illuminated #400TL
Rubber eyeshields
Knurled diopter
adjustment
Post locking
knob
Focusing knob
Post
Light control
switches
Fuse