[1] In June 1988, Canon announced the EF 50-200mm f/3.5-4.5L lens.
This lens has very similar physical qualities compared to the EF50-200mm f/3.5-4.5.
Aside from the different optical construction and slight variation in weight and length, the L and non-L lenses were basically identical.
Note that at this time period Canon did not protect its L zooms against adverse elements such as weather.
Both this lens and the similar duo EF 100-300mm 5.6 and its L variant lacked weather sealing construction, sharing the same housing as their non-L counterparts.