Casio announced last week in Japan that it will release a second set of theme-color 30th anniversary model G-SHOCK watches on January 25, 2013. The six new models are called “Initial Blue”, with the black base color and blue liquid crystal displays and buttons signifying a new dawn in the era of G-SHOCK.

The G-SHOCK brand started from a simple idea: create a watch that is virtually unbreakable. The original shock-resistant model was released in 1983. By overturning the idea that wristwatches are fragile and easily breakable, G-SHOCK created a whole new market for tough watches. Since that time, the brand has continued to evolve in pursuit of even greater toughness.

Each of the six anniversary models has its own unique features.

• The GA-113B-1AJR features a big face and is equipped with a 1/1000-second stopwatch.
• The GA-303B-1AJR has a retro-style design with a wheel-motif sub-dial.
• The GW-9230BJ-1JR is equipped with the Tough Solar battery charging system.
• The GB-5600AA-A1JR and GB-6900AA-A1JR are compatible with Bluetooth® v4.0 (Bluetooth low energy wireless technology).
• The MUDMAN GW-9330B-1JR is dust- and dirt-resistant, and has twin censors for compass bearing and temperature.
• Each watch comes with a special custom package. (Pictured)

The new models will be priced between 18,000 and 40,000 yen (before tax).