Screw clamps. Screw clamps are types which use a screw mechanism to adjust the jaws and clamp a workpiece in place. The types which are found in the screw clamp category include G clamps (also known as C clamps), F clamps, edging clamps, wooden hand screw clamps and rack clamps.
Dry drowning usually happens soon after exiting the water, but with secondary drowning, there can be a delay of up to 24 hours before the person shows signs of distress. Both can cause trouble breathing and, in worst-case scenarios, death.
With dry drowning, water never reaches the lungs. Instead, breathing in water causes your child's vocal chords to spasm and close up after he's already left the pool, ocean, or lake. That shuts off his airways, making it hard to breathe. Secondary drowning happens a little bit differently.