====== Sinn 303 M ======
{{wst>image_r|Sinn_303_M|Sinn 303 M km-h}}
{{wst>image_r|Sinn_303_M_Silber|Sinn 303 M-mph Silver}}
{{wst>image_r|Sinn_303_M_RS|Sinn 303 (back)}}
The **303 M** is a model railroad [[chronograph]] by [[Sinn]].

The tachymeter of this chronograph is matched to a model railway. Thus, the speed of a fast model ICE can be measured as exact as that of a historic steam locomotive. A sympathetic additional function, that makes this watch an original and personal property of every true model railroader.

Variants With mph classification and date in the English language; with [[guilloché]], galvanized silver dial.


<WRAP ud ud_mod>

**Movement:**
  * Mechanical [[chronograph]] movement [[Valjoux 7750]], 28.800 A/h
  * [[Automatic]]
  * [[Nivarox]] 1 hairspring, [[Glucydur]] [[balance wheel]], Berylium plateau
  * [[Antimagnetic]] according to DIN 8309
  * [[Shock proof]] according to DIN 8308

**Case:**
  * [[Stainless steel]] bracelet, DIN material No. 1.4435, polished, tachymeter ring [[satin-finished]]
  * Ø 41 mm, height 16.5 mm
  * [[Sapphire crystal]], with [[anti-glare treatment]] on the inside
  * [[Sapphire crystal]] caseback with printing measured sections and standards
  * (Optional ) Dehumidifying technology by filling the case with noble gas argon and patented dry capsule
  * [[Screw-in crown]] with double o-ring gasket, with crown protection
  * Pushers with double O-ring seal and pusher protection
  * [[Waterproof]] to 200 m
  * Safe below atmospheric pressure

**Dial:**
  * Black mat or silber
  * [[Guilloché]] and elaborate silver galvanised dial
  * Indexes coated with special long-lasting, luminous paint, fine minute scale
  * External tachymeter scale ring with colored engraving

**Functions:**
  * Hours, minutes, [[small seconds]] with [[hacking seconds]]
  * Date and day of week indication in German (km/h) or English (mph) at 3 o'clock
  * Chronograph 12 hours counter, 30 minutes counter, 60 seconds counter
  * Tachymeter scale for speeds (400 to 2 km/h or 250-1 mph)

**Bracelet:**
  * Black Russia leather strap
  * Variant with massive [[stainless steel]] bracelet and milled [[folding clasp]] and 30 mm overall extension

**Warranty:**
  * 2 years (with Ar dehumidifying technology 3 years)
</WRAP>

{{tag>Watch_models Chronographs Sinn_Instrument_Chronograph_models}}