The ultimate manhole covers site
and are usually round
, though square covers
were also found.
, while others belong to communication companies such as Keystone Telephone Company
or Level 3 Communications
.
. The function of others can be determined according to the consumer’s name: electricity (PECO Philadelphia)
, the word STEAM for heating or gas covers
, and so on.
and Clark’s Foundry, also American
.
PECO Philadelphia (2)
,
Keystone Telephone Company (1)
,
Level 3 Communications (1)