<PAGE>
EXHIBIT 21
SUBSIDIARIES
The Registrant, Bolt Technology Corporation, a Connecticut Corporation, has no
parent.
The following are the subsidiaries of the Registrant
(at June 30, 2000)
State of
Incorporation
-------------
Bolt International Corporation Connecticut
Bolt Export Corporation United States,
Virgin Islands
Custom Products Corporation Connecticut
A-G Geophysical Products, Inc. Texas
The names of certain subsidiaries are omitted since such subsidiaries considered
in the aggregate would not constitute a significant subsidiary at the end of the
year covered by this report.