A plain oblong tray was standard, first in sand-cast, and latterly in gravity die-cast aluminium. The dimensions were 4 1/4" x 6 3/4", with 1" high sides all round in each variety.
Some had cast aluminium drawbars, but latterly most drawbars were 3/16" diameter rod cast into the body and bent at the end. The wheels were 1 3/4" diameter black rubber on 3/16" axles for both two and four wheelers.
A variety of Large Trailers are displayed with different styles of drawbars and axle spigots.
Click on the thumbnails to enlarge...