A screw crown watch features a crown that can be screwed down against the watch case to enhance water resistance. This design helps to prevent moisture and dust from entering the watch, making it ideal for diving and other water-related activities. The crown must be unscrewed to set the time or wind the watch, ensuring a secure seal when not in use. This feature is commonly found in many high-end and professional dive watches.
I own an AT0875-09E, and can report that the crown does not screw down, although the watch is WR200. I have swum with it with no problems.
crown: Also called a stem or pin, a crown is the knob/button on the outside of the watch case that is used to set the time and date. In a mechanical watch the crown also winds the mainspring. In this case it is also called a "winding stem". A screw in (or screw down) crown is used to make a watch more water resistant. The crown actually screws into the case, dramatically increasing the water-tightness of the watch.
A crown stopper is a feature found on some watches that prevents the crown from being pulled out inadvertently, thus protecting the watch from water damage. It can be a screw-down crown or a push-in crown with a locking mechanism to secure it in place.
To adjust the time on a Nautica watch, first unscrew the crown (if it's a screw-down type), pull the crown out to the time-setting position, and then turn it clockwise or counterclockwise to adjust the time. Once the correct time is set, push the crown back in and screw it down (if applicable) to ensure water resistance.
To wind a Baume et Mercier automatic watch, hold the watch in one hand and unscrew the crown located on the side of the watch. Gently pull the crown out to the first position and turn it clockwise for about 30-40 turns. Push the crown back in and screw it back tightly. Your watch should now be wound and ready to wear.
To change the watch crown, the back of the watch must be taken off. The inner workings of the watch are then removed, and the old crown taken out. The process is reversed to put the watch back together. Some of the fancier watches have a crown that can be unscrewed from the outside.
Crown, cap, or head.
On the right hand side of your watch is a small knob. Pull gently on this knob. It should pull out to 2 different positions. The first position sets the date; the second sets the time. Move the knob and the time will change.
Rolex
To set the time on your TechnoMarine watch, first locate the watch crown on the side of the watch. Pull the crown out to the appropriate position (usually position 2 for time setting) and then turn the crown to adjust the hour and minute hands to the correct time. Once you have set the time, push the crown back in to secure the settings.
To set the time on a Charles Raymond watch, locate the crown on the side of the watch. Pull the crown out to its second position and rotate it to adjust the time. Once the correct time is set, push the crown back in to its original position.
To set the Athletic Works AW150 watch, first, pull the crown out to the second position to adjust the time. Rotate the crown to set the hour and minute hands. For the date, pull the crown to the first position and turn it to change the date. Once set, push the crown back in to start the watch.