194 / | HD | CHECK-ACTUATED CONTROL MECHANISMS |
302 | DF | INCLUDING MEANS TO TEST VALIDITY OF CHECK {4} |
328 | .~ Having means to test surface configuration {4} | |
329 | DF | .~.~> Raised annular rim |
330 | DF | .~.~> Both faces of check |
331 | DF | .~.~> Serrated edge |
332 | DF | .~.~> Apertured check {1} |