What makes a Sempra automatic watch different from a standard watch?
Instead of relying on a battery or electronic circuit, a Sempra automatic watch runs entirely on mechanical engineering. It uses the kinetic energy created by your wrist's natural movement to power itself throughout the day.

Automatic vs. Quartz: Why should I choose mechanical?
While quartz watches run on batteries and tick once per second, an automatic mechanical watch is a piece of traditional craftsmanship. It features a sweeping second hand and operates purely on gears, springs, and the movement of your body. Choosing Sempra means wearing a living piece of micro-engineering on your wrist.

Will I ever need to replace the battery?
Never. Since every Sempra timepiece is fully mechanical, there are absolutely no batteries inside to replace or leak over time.

Which movements are used in Sempra watches?
We source premium Japanese automatic calibers for our collections. Depending on the specific model you choose, your watch will be powered by either the Seiko NH38 or the Epson/Orient YN55.

Why do you use the NH38 and YN55 calibers?
Both are known throughout the watchmaking industry as incredibly reliable workhorses. We use the NH38 for Sempra designs featuring no-date or open-heart dials, while the YN55 is selected for its high winding efficiency and solid out-of-the-box accuracy.

Do these movements have hacking and hand-winding features?
Yes, they do. Hacking stops the second hand when you pull the crown out, letting you set the time down to the exact second. Hand-winding allows you to manually power your Sempra watch by simply turning the crown.

How long will the watch run if I take it off?
The power reserve for both the NH38 and YN55 is roughly 40 hours. If you leave your Sempra sitting on a desk for the weekend, you'll just need to give it a quick manual wind to get it ticking again on Monday.

How accurate are Sempra mechanical watches?
They are factory-regulated to operate within an expected range of -20 to +40 seconds per day. Keep in mind that mechanical watches are sensitive instruments; their daily accuracy can fluctuate slightly depending on how active you are and the position the watch rests in overnight.

Is it possible to overwind an automatic watch?
Not with our movements. A Sempra automatic watch has a built-in slipping mainspring. Once the mechanism is fully wound, it simply slips inside the barrel to prevent any excess tension, so you can't damage it by turning the crown too much.

What is the Sempra watch case made of?
We use 316L surgical-grade stainless steel for every Sempra case. This specific grade provides excellent resistance to corrosion, pitting, and the daily wear and tear of regular use.

Is the crystal scratch-resistant?
Protecting the dial is crucial, so your Sempra comes equipped with either sapphire or hardened mineral crystal, depending on the specific collection. Both are designed to handle impacts and keep the watch face clear.

Can I read the time in the dark?
Absolutely. Most Sempra models feature luminous paint applied to the hands and hour markers. This material charges up from ambient light during the day and glows visibly in low-light environments.

Can I change the strap on my Sempra?
Definitely. We design Sempra watches with standard lug widths. This makes it incredibly easy to swap out the original steel bracelet or leather strap for a NATO band or any other aftermarket strap that fits your personal style.

How do I start my Sempra watch for the first time?
When you first unbox your Sempra, it won't have any power stored. Just unscrew or pull the crown out to the first position and rotate it clockwise about 20 to 30 times. This fully charges the mainspring so you can set the time and wear it.

Are these watches safe to use in water?
Each Sempra watch has a specific depth rating (such as 50m, 100m, or 200m). Before getting it wet, you must double-check that the crown is securely pushed all the way in or screwed down tightly against the case.

What is the best way to clean my watch?
A soft microfiber cloth is perfect for wiping smudges off the crystal and case. For a deeper clean on a Sempra steel bracelet, you can use a soft toothbrush with a bit of mild soapy water—just make sure the crown is sealed completely beforehand.

My watch is suddenly running very fast. What happened?
It is highly likely your Sempra watch has become magnetized from resting near a laptop speaker, tablet, or strong magnet. It’s a common issue with mechanical watches and is easily fixed by a local watchmaker in a few seconds using a demagnetizer.

How often should I get it serviced?
Because Japanese automatic calibers are notoriously tough, your Sempra won't need constant check-ups. We recommend a standard professional service—which includes cleaning and re-lubricating the movement—every 5 years.

What does the warranty cover?
We stand strictly behind our build quality. Your Sempra watch includes a warranty that covers any manufacturing defects and internal movement malfunctions under normal, everyday use.

Do you offer international shipping?
Yes, Sempra ships to watch enthusiasts all over the world. Shipping costs and delivery estimates are calculated at checkout based on your exact location.

What if I want to return my purchase?
If your Sempra isn't exactly what you hoped for, you can send it back. We offer a clear return window as long as the timepiece remains completely unworn, unsized, and is returned in its original packaging.

How do I know if a Sempra watch will fit my wrist?
We design our watches to fit a wide variety of wrist sizes. On each product page, you will find detailed specifications including the case diameter (e.g., 40mm) and the lug-to-lug distance. Generally, our watches comfortably fit wrists ranging from 6.2 inches to 8.2 inches.

Can I adjust the steel bracelet myself?
Yes. Our stainless steel bracelets come with removable links so you can get the perfect fit. While you can adjust it at home with a standard watch pin tool, we highly recommend taking it to a local jeweler or watchmaker for a quick and professional sizing to avoid scratching the metal.

Will I be charged customs duties or import taxes?
For international orders, your shipment may be subject to import taxes, customs duties, and fees levied by the destination country. These charges are the buyer’s responsibility. We recommend checking your local customs policies before placing an international order.