Hamilton Khaki Scuba H82345341 (Blue, 40mm)

How long does the 80-hour power reserve actually last?

The H-10 movement provides approximately 80 hours of continuous operation when fully wound. This means if you remove the watch on Friday evening, it will still be running on Tuesday morning. The power reserve indicator isn't visible on this model, but you can feel the automatic rotor winding as you wear it. For maximum power reserve, wear the watch for at least 8-10 hours daily or give it 30-40 manual winds when first setting it up.

Can I swim and shower with this watch regularly?

Yes, the 100-metre water resistance rating makes it suitable for swimming, showering and snorkelling. However, avoid operating the crown underwater as this can compromise the seal. The screw-down crown should be fully tightened before water exposure. After saltwater use, rinse the watch with fresh water to prevent mineral buildup. Avoid hot showers as temperature changes can affect the seals over time.

What makes the sapphire crystal better than regular watch glass?

Sapphire crystal ranks 9 on the Mohs hardness scale, making it virtually scratchproof in daily use. Only diamond can scratch sapphire, so keys, coins and normal wear won't damage the crystal surface. The anti-reflective coating reduces glare by up to 99%, improving readability in bright conditions. Unlike mineral glass, sapphire won't develop the fine scratches that cloud visibility over time, maintaining crystal clarity for years.

How accurate is the automatic movement?

The H-10 automatic movement typically runs within -10 to +15 seconds per day when fully wound and worn regularly. Accuracy depends on your activity level, wrist position and how consistently you wear the watch. New automatic watches may need a few weeks to settle into their optimal accuracy range. If the watch runs outside these parameters, it may need professional regulation by an authorised Hamilton service centre.

What size wrist does the 40mm case suit best?

The 40mm case diameter works well for wrist sizes from 15cm to 20cm circumference. The 20mm lug width and moderate 13mm thickness create balanced proportions that don't overwhelm smaller wrists or appear undersized on larger ones. The rubber strap adjusts to accommodate various wrist sizes comfortably. For reference, this size typically suits most adult wrists, though personal preference for larger or smaller watches varies.

Does the blue rubber strap cause skin irritation?

The rubber strap uses hypoallergenic materials designed for extended skin contact. However, some people may experience irritation if moisture gets trapped underneath. To prevent this, remove the watch occasionally to let your skin breathe, especially after swimming or intense exercise. Clean the strap regularly with mild soap and water, ensuring it's completely dry before wearing. If irritation occurs, consider alternating with a different strap material.

How do I set the time and date correctly?

First, unscrew the crown by turning it anticlockwise until it pops out. Pull the crown to the first position to set the date - turn clockwise to advance the date. Pull to the second position to set the time - turn in either direction to adjust hours and minutes. Avoid setting the date between 9 PM and 3 AM as this can damage the movement. Push the crown back in and screw it down clockwise to ensure water resistance.

What warranty coverage does Hamilton provide?

Hamilton provides a two-year international warranty covering manufacturing defects in materials and workmanship. This includes movement malfunctions, case defects and crystal issues under normal use. The warranty doesn't cover damage from accidents, water ingress due to crown misuse, or normal wear items like straps. Keep your purchase receipt as proof of purchase date. Warranty service must be performed by authorised Hamilton service centres to maintain coverage.