Rolex
Datejust 31
m278240-0002
On this page you can read about Rolex model Datejust 31 m278240-0002. All the technical specifications like case material, case diameter and calibre attributes like movement type, power reserve etc. are listed here in an easy to understand tabular format. There are also images of Datejust 31 m278240-0002. At the bottom of the page you can find similar watches from Rolex.
Important facts
The Rolex Datejust 31 m278240-0002 has a screw-down crown which ensures a much better water resistance by providing a tighter seal between the crown and the case. This keeps moisture or dust from entering the watch case, which could otherwise cause damage to the movement. This also helps to prevent accidental adjustment of the time or date. The screw-down feature makes it more difficult for the crown to be accidentally turned, reducing the risk of incorrect timekeeping. Also, it is a reassuring feel to tighten the crown by screwing it down.
This watch has an automatic mechanical movement, which stores power in a mainspring, that is wound by an oscillating rotor while the watch is being worn. A mechanical watch movement is less accurate than a quartz one and requires regular servicing. It does not need a battery though and has a smoother sweeping seconds hand.
This timepiece has a sapphire crystal which provides a durable and clear viewing surface for the dial. This type of crystal is highly resistant to scratches and does not discolor over time. Sapphire is also resistant to most chemicals and less likely to shatter compared to other materials, making it a safer choice for the watch wearer. Thefore sapphire is a good choice for high-end wristwatches. It is of course an expensive option, compared to other materials, like plexiglass.
The case of the Datejust 31 reference m278240-0002 is made out of stainless steel which is a strong and durable material, therefore being resistant to scratches, dents, and general wear and tear. Steel is also highly resistant to corrosion and rust, but is also a hypoallergenic material, which means that it is less likely to cause skin irritation or allergic reactions. Let's not forget the versatility of steel, which makes this watch pair well with several different attires.
The Rolex Datejust 31 m278240-0002 is a chronometer, certified by COSC, the Official Swiss Chronometer Testing Institute. The testing involves a series of measurements over a period of 15 days in different positions and temperatures to ensure the watch's accuracy.
Technical specifications
| anti magnetic | hairspring |
| bezel style | domed |
| bracelet material | stainless steel |
| bracelet style | jubilee |
| case back locking | screw down |
| case diameter | 31 |
| case material | stainless steel |
| clasp type | folding |
| date magnifier | |
| dial color | black |
| front crystal material | sapphire |
| manufacturer case material | oystersteel |
| manufacturer case name | oyster |
| manufacturer cert | rolex |
| screw down crown | |
| water resistance meter | 100 |
Calibre specifications
| anti shock | balance wheel |
| bidirectional winding | |
| calibre in house | |
| calibre no | 2236 |
| calibre precision minus | 2 |
| calibre precision plus | 2 |
| calibre type | mechanical |
| center seconds | |
| chronometer | cosc |
| hackable | |
| instant date change | |
| power reserve | 55h |
| quick set date | |
| winding mechanism | automatic |
Images
