Antoninus Pius Æ As. Struck 145-161 AD. 18.39g; 28mm.

ANTONINVS AVG PIVS P P TR P COS IIII, laureate head right.
SECVRITAS PVBLICA S-C, Securitas standing left, holding long sceptre. 
Cohen -, RIC -, BMC 1765. 
RIC notes only Securitas leaning on column.

Very large and uncommonly heavy module.

With permission of Roma Numismatics, October, 2011