View source for JLC 975

The '''JLC 975''' is a watch movement from [[Jaeger-LeCoultre]]. Dubbed the '''Autotractor''', it was the first of a new family of rugged movements and was introduced in [[2004]].

The 975 is an [[automatic]] [[dual timezone]] movement made up of 230 pieces. It runs at 28800 vph, has 29 jewels, and a power reserve of 48 hours. This new movement family uses ceramic ball bearings for the rotor, increasing durability and extending the service interval. It also lacks the bidirectional winding gearing found on most earlier Jaeger-LeCoultre movements, favoring a unidirectional rotor for durability and improve power transmission. The balance spring is a new design supplied by [[Richemont]] sister company [[A. Lange & Söhne]] and is laser welded to the balance. Rather than a regulation index, the balance is adjusted by means of four screws, and the balance cock has been replaced by a screwed bridge. 

There are two current versions of the basic JLC 975 movement, differing mainly in their implementation of the [[dual timezone]] function:
* The '''JLC 975H''' shows the second timezone using both a [[24-hour]] subdial and a skeleton hour hand co-axial with the main hour hand. It also supports subdial seconds.
* The '''JLC 975D''' uses only the 24-hour subdial for the second timezone and omits the seconds subdial altogether.

The 972 is similar to the 975 but adds a "Dualmatic" feature that allows the 24 hour coaxial dial to be repurposed as a minute counter using a second crown. 

==Applications==

Jaeger-LeCoultre currently uses this calibre in 5 watches.
* [[Jaeger-LeCoultre Master Compressor GMT]] (JLC 975H)
* [[Jaeger-LeCoultre Master Compressor Diving GMT]] (JLC 975D)
* [[Jaeger-LeCoultre Master Compressor Diving GMT 46.3mm]] (JLC 975D)
* [[Jaeger-LeCoultre Master Hometime]] (JLC 975H)
* [[Jaeger-LeCoultre Master Hometime Aston Martin]] (JLC 975H)

==External Links==

* [http://www.qpmagazine.com/media/39479/Back_to_Basics_Jaeger_LeCoultre.pdf Jaeger-LeCoultre’s new movement finds a welcome home]
* [http://www.thepurists.net/Patrons/Members/wsw/jlc_at/jlc975finweb.htm Jaeger - Le Coultre caliber 975]

{{WD|
'''Manufacturer:'''
:[[Jaeger-LeCoultre]]

'''Description:'''
:[[Automatic]] movement
:230 components

'''Functions:'''
:Hour/minute
:[[Small seconds]]
:[[24 hour]] subdial
:[[GMT]]
:Date
:[[Operating indicator]]

'''Data:'''
:H 5.70 mm
:29 [[jewels]]
:28800 A/h
:Power reserve 48 Hours

'''Production period:'''
:Current
}}

[[Category:Movements]]
[[Category:GMT movements]]
[[Category:Automatic movements]]
[[Category:Jaeger-LeCoultre calibres|975]]
[[Category:Jaeger-LeCoultre Autotractor calibres|975]]