A railroad may not place or continue in service a car, if—

(a) The car has a draft gear that is inoperative;

(b) The car has a broken yoke;

(c) An end of car cushioning unit is—

(1) Leaking clearly formed droplets; or

(2) Inoperative;

(d) A vertical coupler pin retainer plate—

(1) Is missing (except by design); or

(2) Has a missing fastener;

(e) The car has a draft key, or draft key retainer, that is—

(1) Inoperative; or

(2) Missing; or

(f) The car has a missing or broken follower plate.