SEIKO Diver SSA055 Automatic Watch
Overview
The Seiko SSA055 (4R37-00F0) is a 43mm men's automatic watch with a stainless steel case and a green analog dial protected by hardlex crystal. It uses a 4R37 caliber self-winding mechanical movement that can be manually wound and hacked (the second hand stops when the crown is pulled out). It ticks 6 times per second which gives the second hand a smoother movement than quartz watches which tick once per second. The watch should run for up to 41 hours when fully wound and will self-wind when moved.
The SSA055 is currently ranked #135 in popularity out of 751 watches in this catalog. Check availability on Amazon.com. This watch is part of a family of seven watches that are identical except for their color or strap. You can see the other variations in this family as well as other similar models on the left side of the page. By clicking the checkbox under a similar model you can compare that model with this one side-by-side. We use nearly 100 different weighted criteria to calculate which models are the most similar to one another.
SSA055 is only a partial model number. [learn more]
The case of the SSA055 measures approximately 43mm wide (not including the crown) by 13mm thick and is water resistant to 100 meters. This should be sufficient for splashes, rain, baths, showers & swimming (shallow diving) but is not recommended for scuba diving. The crown does not screw down which increases the risk that it could be pulled out accidentally while under water. The watch has a display back to show of the 4R37 movement.The stainless steel bezel shows minute numbering and can be rotated. The inner bezel can be rotated using the second crown to adjust the compass directions. The gap between the lugs is 22mm and the canvas band can be removed using a band removal tool to be replaced with another band.
The SSA055 provides the following features and complications:
- Second hand
- Minute hand
- Hour hand
- 24 hour subdial to show if it is morning or night
- Date window to show the day of the month. Note that some watches may be damaged if you attempt to change the date between 8:00 PM and 2:00 AM, in which case you should change the time to be outside that range first then reset the time after adjusting the date. Check your watch manual for details.
- Rotatable bezel
- Rotatable inner bezel
Seiko Date Finder
If you have this watch and want to know when it was made simply enter the six digit serial number from the caseback below then click Find Date. Learn more
Specifications [edit]
Full specifications are listed below. Please report any errors by clicking the edit link above then use the appropriate 
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General
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Search: eBay | Chrono24 - Popularity
#135 of 751 - Style Military / Field, Diver
- Gender Men's
Movement
- Type Automatic
- Caliber 4R37
- Jewels 24
- Beats per Hour 21,600 bph(6 bps)
- Power Reserve 41 Hours
- Manual Winding Yes
- Hacking Yes
- Instructions Owner's Manual
Case
- Case Width
43mm(without crown) - Case Thickness 13mm
- Case Shape Round
- Case Material Stainless Steel
- Case Code 00F0
- Crystal Material Hardlex
- Water Resistance 100 Meters(baths & shallow diving)
- Crown Position 04:00
- Screw Down Crown No
- Second Crown Yes
Complications
- Second Hand Yes
- Minute Hand Yes
- Hour Hand Yes
- 24 Hour Subdial Yes
- Date Window Yes
Band
- Band Width 22mm
- Replaceable Band Yes
- Band Material Canvas
- Band Color Green
Dial
- Dial Color Green
- Dial Reference
- Hour Markings Bars, Triangles
- Subdial Position 10:00
- On the Dial
"Automatic", Water Resistance
Bezel
- Bezel Color Silver
- Bezel Function Unidirectional
- Bezel Material Stainless Steel
- On the Bezel Minute Numbering
Inner Bezel / Chapter Ring / Outer Dial
- Inner Bezel Color Green
- On Inner Bezel Bars, Compass Directions
Hand Colors
- Hour Hand Black, White
- Minute Hand Black, Red
- Second Hand Black, White
If you see anything that seems incorrect please let us know.
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