====== Seiko 4R15 ======
**4R15** and **4R16** are two related [[automatic]] upper-midrange watch movements from [[Seiko]].

===== Overview =====
The 4R15 family was introduced in [[2008]] as mainstream automatic watch movements for Seiko watches. It is based on the [[hacking]]/[[hand-winding]] [[Seiko 6R15]] but lacks these advanced features. Both of these movement families are based on the basic [[Seiko 7S26]] movement, and all share some components. Unlike the 7S26 family (and the hacking/hand-winding brother, [[Seiko 4R35|4R35/6/7/8/9]]), the 4R15/16 have a long 50 hour [[power reserve]] thanks to an advanced [[Spron]] 510 [[mainspring]]. This is shared with the 6R15 as well.

===== Variants =====
Like most Seiko movements, the 4R15/16 family operate at 21,600 A/h. All models feature sweep hour, minute, and second hands. The 4R15 features a date window, while the 4R16 has both day and date in a window. Both have 22 jewels.

^Movement ^Beat ^Hands ^Date ^Subdial ^Jewels ^Power reserve ^
|4R15 |21,600 A/h |Hour, minute, seconds |Date |None |22 |50 hours |
|4R16 |:::|:::|Day and date |:::|:::|:::|


===== Applications =====
The 4R15 and 4R16 are used in many Seiko "[[Seiko Superior|Superior]]" watches, most in the "[[Seiko SRP|SRP]]" model series. These featured upmarket features from the common [[Seiko 5]] line, such as sapphire crystals and metal bracelets with solid end links.


{{wst>template_seiko_7s_family}}

===== External links =====
  * [[http://watcharama.com/the-seiko-4r36-family-in-brief/|Seiko 4R36 -The Family In Brief]]
  * [[https://reference.grail-watch.com/family/seiko-4r/|Seiko 4R Family Reference]]


<WRAP ud ud_mov>

**Description:**
  * [[Automatic]] movement

**Functions:**
  * Hours, minutes, seconds
  * [[Central seconds]]
  * Rapid calendar advance

**Data:**
  * 22 [[jewels]]
  * 21,600 A/h
  * Power reserve 41 hours
  * [[Spron]] 510 mainspring

**Production period:**
  * [[2008]]-Present
</WRAP>

{{tag>Movements Automatic_movements Seiko_calibres}}