Watanabe Kobo Handmade Watch Open Heart Manual Winding Brass Cushion Case 34mm Arabic Numerals Sewing Machine Stitch Belt [BHW143-MS]

Mr. Masaaki Watanabe of Watanabe Koubou is a watchmaker who makes watches one by one by hand at his workshop in downtown Tokyo. We have worked on many watch works that are full of warmth and a tasteful expression unique to handmade.

Mr. Watanabe does everything by hand, from making watch parts such as cases, dials, and belts to assembling them.

An open heart model that allows you to see the movement of the machine from a part of the dial. It is a soothing work that moves like a human heartbeat.

Accented with a small window where you can see the “heart (machine)” (The belt color in the photo is “camel x beige”)

This watch named "Open Heart" is a hand-wound mechanical watch with a small window on the dial.

The movements of the movement can be seen through the small window, and it looks like a human heartbeat. You will be healed by the sound of the second hand that sounds quietly, "Tick, tick, tick, tick, tick, tick".

The hand-wound type winds the mainspring by turning the crown manually. The back of the case is a skeleton specification, and you can enjoy the movement of the movement that ticks the time.


The size of the case is 34mm, which is slightly smaller than the standard size.
It is a size that is easy to incorporate for both men and women.

The brass case with an antique texture has a taste unique to handmade.
The more you use it, the more antique it will look.

By winding the mainspring fully with the crown on the right side, it will continue to work for a day to a day and a half.

It has a see-through back design, so you can enjoy the movement of the movement on both sides.

Now that hassle-free self-winding and quartz watches have become widespread, more and more watch enthusiasts are choosing manual-winding types that require the work of "winding the mainspring by hand."

The trouble of winding the mainspring by hand is like grinding coffee beans in a mill.

Genuine cowhide with good texture is used for the material of the belt. It has a firm thickness, excellent durability, and an elegant appearance.

Tannin tanned genuine cowhide is used for the belt

The line of the sewing machine stitch becomes the casual accent

buckle part

Whole, front and back (click to enlarge)

The moderate weight of the case and the elegance of the cowhide belt add quality to an adult's outfit. It is also recommended for vintage outfits and work styles.

Perfect for chic styles, neat styles, and antique dresses.
(Female, arm circumference approx. 15cm)

It has just the right amount of presence and can be used for business occasions. (Men, arm circumference approx. 17cm)

It is also recommended as a gift with a "heart".


Moderate size that can be used by both men and women. It is a design that seems to appeal to adults and dignity.

The warm atmosphere of brass goes well with casual styles.

Not only for yourself, but it is also recommended as a gift for birthdays, anniversaries, Christmas, Valentine's Day, White Day, Father's Day, Mother's Day, Respect for the Aged Day, school entrance celebrations and employment celebrations.

You can choose the belt color and stitch color.

sewing machine stitch belt
You can choose from 5 types: camel x beige, dark brown x brown, dark brown x black, black x brown, black x black.

With your favorite belt color, a special one just for you...

We have a slightly larger 38mm case model.

≪Click the image to move to the page≫

Material/Processing/Size

Material/processing	[Movement] Manual winding type, 3 needles [Case] ​​Brass / back cover is stainless steel and glass (back skeleton specification) [Belt] Genuine leather (tannin tanned cowhide), sewing machine stitch [Windshield] Glass
size	[Case] ​​Dial diameter: 29 mm / case: vertical/horizontal maximum width 34 mm / thickness: about 12 mm [Belt] Width: 19mm/Thickness: Approx. 4mm/Compatible arm circumference: 13cm-16.5cm [Weight] about 60g

Points to note when ordering

Most of our products are made-to-order, so it takes about 3 weeks to 1 month for delivery. Christmas, Valentine's Day, and the gift season before White Day tend to take longer to produce. If you are thinking of giving it as a gift, please consider the delivery date before ordering.

The warranty period is one year from the date of purchase. However, only internal failures are covered by the warranty, and external parts such as cases and belts are not covered by the warranty.

It is not waterproof, so please be careful when working on rainy days or around water.

Since it is a hand-wound watch, it will stop unless the mainspring is wound up. Please note that winding the mainspring too much may cause it to break.

A hand-wound watch does not have a second hand stop function. The second hand does not stop when setting the time.

The color may change depending on the color of the case and belt, such as eyelets and buckles. We would appreciate it if you could order it after understanding that it is one of the features and charms of handmade watches.