How to Change the Strap on a Dive Watch

Dive watches are built to be tough, and that extends to how their straps attach. Thick cases, tightly fitted curved-end straps and, on some models, screw bars instead of spring bars mean that a strap change on a diver can be a little more involved than on a dress watch. None of it is difficult once you know what you are dealing with. This guide explains how to identify your watch's attachment type, which tools you need, how to do the swap safely, and what to look for in a strap you plan to wear in and around water.

Step 1: Identify how your strap is attached

Before you pick up a tool, work out which of these systems your watch uses. Look closely at the outside of the lugs.

• Standard spring bars, no holes on the outside of the lugs. The most common setup. The bar is removed from between the strap and the lug using the forked end of a spring bar tool.
• Drilled lugs. Small holes go all the way through the lugs. You can push the spring bar tips in from the outside with the pin end of the tool, which is quicker and less likely to scratch the case.
• Screw bars. You will see a tiny screw head on the outside of one or both lugs. These bars must be unscrewed, usually with a very small hex key or screwdriver. A spring bar tool will not work. The Blancpain × Swatch Scuba Fifty Fathoms is one example of a watch that uses screw bars.
• Quick-release bars. A small lever on the bar itself, usually found on aftermarket straps. Slide the lever and the bar retracts.
• Integrated straps or bracelets. Some straps are shaped to fill the space between the lugs completely and may attach to the bracelet's folding clasp. These still use bars at the case, but the fit is tighter and the strap must be made for your specific model.

Tools you will need

• Spring bar tool with both a forked end and a pin end.
• Precision hex keys or screwdrivers in the size your screw bars require, if your watch uses them.
• A soft cloth or mat to protect the crystal and bezel.
• Low-tack tape (optional) to protect polished lugs.
• A small dish for screws and spare bars – screw-bar parts are tiny and easy to lose.

Step 2: Remove the old strap

Spring bars without drilled lugs

1. Lay the watch face down on the cloth.
2. Slide the forked end of the tool between the strap and the inside of the lug until it catches the shoulder of the bar.
3. Compress the bar toward the center and lift the strap end free of the lug.
4. Repeat on the other side.

Thick dive straps and fitted ends can make the bar hard to reach. Pressing the strap material gently back from the lug, or working from the underside, gives the tool more room.

Drilled lugs

Place the pin end of the tool into the outer hole, press inward to push the bar tip out of the lug, and lift that side of the strap. The other side then slides out.

Screw bars

1. Hold the watch securely on its side on the cloth.
2. Fit the correct driver into the screw head and turn counter-clockwise. On some designs both ends are screws, so hold one side still while turning the other.
3. Withdraw the bar and set every part in your dish.

Use the correct size driver. An undersized tool can strip the tiny screw head.

Step 3: Fit the new strap

Re-fit using the reverse of the removal steps. A few dive-specific points:

• Use the right bars. If your watch uses screw bars, the new strap must be able to accept them. Many aftermarket straps arrive with spring bars already fitted, which you may need to remove first.
• Orientation of curved ends. The concave side faces the case. If the strap seems not to fit, check it is the right way round before pushing harder.
• Snug is normal. Fitted dive straps are designed to fill the gap tightly. Angle the strap slightly while seating the second end, then let it rotate into place.
• Screw bars and thread-locker. Some owners add a tiny amount of low-strength thread-locker to screw bars so they do not back out over time. Use it sparingly, if at all, so the bar can still be removed.

Step 4: Check before you wear it

• Give each strap half a firm, steady pull while holding the case.
• Look from the side: spring bar tips should sit fully inside the lug holes.
• For screw bars, confirm the screws are snug, but not over-tightened.
• Re-check everything after the first wear. Straps settle, and it is better to catch a loose bar at your desk than in the water.

Choosing a strap for water use

A dive watch is often worn in exactly the conditions where a strap failure matters most, so a few features are worth looking for:

• Material. Rubber-family straps do not absorb water and dry quickly. Our guide to rubber vs FKM explains how the different compounds compare.
• A secure buckle and keepers. Two keepers, or one fixed and one floating keeper, help hold the strap tail in place during activity.
• Length. If you wear the watch over a wetsuit sleeve, you will need more strap length than for bare-wrist wear. Check the strap's length and hole range before buying.
• Backup retention. A single-pass or pass-through strap threads under both bars, so the watch stays on the strap even if one bar fails. Some divers prefer this setup for that reason.

For context, ISO 6425, the international standard for divers' watches, includes a test of how well the strap or bracelet attachments resist pulling forces. Whatever strap you fit, keep the attachment in good condition.

Care after salt water and pools

• Rinse the watch and strap in fresh water after every swim, paying attention to the lugs and spring bars where salt and sand collect.
• Dry the strap with a soft cloth, and let the lug area air-dry fully.
• Inspect spring bars from time to time. Replace any bar that looks bent, corroded or does not spring back firmly.
• Changing a strap does not open the watch case, so it does not affect the watch's water resistance. However, follow your watch maker's guidance on servicing and pressure testing.

Find a strap for your dive watch

Browse straps compatible with the Rolex Submariner, including integrated rubber straps designed to use the folding clasp from your existing bracelet, or straps compatible with the Blancpain × Swatch Scuba Fifty Fathoms. For other divers, start with our 20 mm and 22 mm straps and check the lug width and fit on each product page.

Rolex, Submariner, Blancpain, Swatch and Fifty Fathoms are trademarks of their respective owners. Brand and model names are used only to describe compatibility. Lugline is an independent brand with no affiliation to any watch manufacturer.