Seiko Speed-Timer Chronograph Automatic Big Blue Kakume Day Date 6138-0030

Brand: Seiko

Model: Speed-Timer Kakume (International Version)

Reference Number: 6138-0030

Serial Number: 47xxxx

Movement: Automatic and hand winding  ( can be wound by rotor or crown)

Caliber: 6138B

Power Reserve: ~45 hours

Number of Jewels: 23

Frequency: 21,600 bph

Production Year: 1974

Case Material: stainless steel

Case Diameter: 43mm x 45mm

Caseback: Screwdown

Thickness: 15mm

Water resistance:

Bezel: Fixed blue with silver Tachymeter markers

Crystal: Hardlex 

Dial: Blue

Dial numerals: None

Hands: Baton

Crown: Push/Pull

Bracelet material: Leather 

Lug width: 18mm

Clasp: Buckle

Functions: 

Time Display: central hours and minutes.

Automatic Winding: The watch is self-winding through an internal rotor, meaning normal wrist movement powers it.

Manual Winding: Unlike the 6139 movement, the 6138 also allows for manual winding via the crown.

Day and Date Display: Features a day and date window at the 3 o'clock position. The international version typically displays the day in two languages (e.g., English and a second language like French or Spanish).

Quickset Day/Date: Both the day and date functions can be set quickly by pushing in the crown at different levels or rotating it when pulled out to a specific position.

Chronograph: This is the main complication, controlled by a column wheel and vertical clutch mechanism. The chronograph functions include:

Central Chronograph Second Hand: A large central hand (typically orange or yellow) that measures seconds when the chronograph is activated.

30-Minute Register: A sub-dial (at the 6 o'clock position on the "Big Blue" model) that counts up to 30 minutes of elapsed time.

12-Hour Register: A sub-dial (at the 12 o'clock position on the "Big Blue" model) that counts up to 12 hours of elapsed time.

Tachymeter Scale: The watch has a fixed bezel with a tachymeter scale, which can be used to measure speed over a known distance. 

Condition: Good pre-owned condition, shows visible signs of wear but all functions are working. Blue leather aftermarket strap

Accessories: Gift box

Comes with our One Year Limited Warranty