# How to Install & Size a No-Pass Parachute Watch Strap (Marine Nationale Guide)

**By Michael Seals** · 2026-03-08

A quick, no-nonsense guide to getting the fit right, keeping the case low, and staying comfortable all day.

Elastic parachute straps, often called Marine Nationale style straps, are popular for good reason. They are light, secure, and extremely comfortable. The no-pass format keeps the watch sitting lower on the wrist than a traditional pass-through strap, a real win for everyday wearability.

In this guide

-   [What is a no-pass parachute strap?](#what-is)
-   [What you need](#what-you-need)
-   [Installation steps](#install)
-   [Sizing and fit tips](#sizing)
-   [Common mistakes](#common-mistakes)
-   [FAQ](#faq)

## What is a no-pass parachute strap?

A no-pass parachute strap is a single-layer elastic strap inspired by the classic Marine Nationale design. Unlike a traditional pass-through strap, it does not run underneath the watch head, the result is a lower profile on the wrist with less bulk.

![Solid navy blue no-pass parachute elastic watch strap from Seals Watch Co.](https://cdn.shopify.com/s/files/1/1004/4894/files/IMG_0528_1_800x.jpg?v=1766334481)

-   **Lower on the wrist:** no extra layer under the case.
-   **Micro-adjustable:** elastic plus hardware dials in the fit without holes.
-   **Easy to wear:** comfortable in heat, during activity, and day to day.

## What you need

-   Spring bar tool
-   Your no-pass parachute strap
-   Two spring bars (included with Seals straps)

## Installation steps

[![Diagram showing how a no-pass parachute strap attaches to each side of the watch case.](https://cdn.shopify.com/s/files/1/1004/4894/files/strap-guide-no-pass_800x.png?v=1766333893)](https://cdn.shopify.com/s/files/1/1004/4894/files/strap-guide-no-pass.png?v=1766333893)

How the strap anchors at 6 and 12 o’clock. Tap to enlarge.

1

### Anchor the 6 o’clock side

Slide a spring bar through the **stitched loop** on one end of the strap. Position that end between the lugs at the **6 o’clock** side of the case and seat the spring bar into the lug holes.

2

### Install the 12 o’clock side

Take the other end of the strap and place it between the lugs at **12 o’clock**. Insert the spring bar and secure it. The watch head is now attached on both sides and the strap forms a continuous loop.

3

### Put it on and connect the hook

Put the watch on your wrist. Pull the strap to your preferred tension, then connect the metal **hook** to the **adjustment slider**. The slider lets you fine-tune the fit quickly and easily.

## Sizing and fit tips

The best fit is snug enough that the watch does not rotate, but relaxed enough that you can slip a finger under the strap. Elastic straps work best with **light tension**, not maximum stretch.

![Seals Model B on a Marine Nationale parachute strap, shown on the wrist.](https://cdn.shopify.com/s/files/1/1004/4894/files/IMG_2255_800x.jpg?v=1772606021)

### How tight should it be?

-   **Too loose:** the watch head drifts and rotates.
-   **Too tight:** the strap feels springy and fatigues your wrist over a long day.
-   **Just right:** stable watch head, comfortable movement, no pinching.

In heat or during activity your wrist can expand slightly, and the elastic accommodates this naturally. After a few wears you will settle on your ideal set point.

## Common mistakes

-   **Twisting the strap between the lugs:** creates hot spots and uneven tension.
-   **Placing the hook too far from the slider:** reduces adjustability and feels awkward.
-   **Over-tightening:** elastic is meant to move with you, not fight you.

## Want more options?

Browse the full Seals parachute strap lineup:

[Shop parachute straps](https://seals-watches.com/collections/elastic-parachute-single-piece-watch-straps)

## FAQ

Does a no-pass strap go under the watch case?

No. A no-pass strap attaches to each side of the case and does not run underneath the watch head.

Will a no-pass parachute strap work with dive watches?

Yes. The secure fit and quick-drying elastic construction make it a great match for dive and sport watches.

Can I wear it in the water?

Yes. Elastic parachute straps are designed for active use, dry quickly, and handle repeated water exposure well.

Why does the no-pass design feel lower than a pass-through strap?

Because there is no extra material layer underneath the case. That reduction in thickness keeps the watch closer to the wrist.

What is the best way to size it?

Set it so the watch does not rotate, then back off slightly until it feels natural. You should be able to slide a finger under the strap comfortably.

Do I need special tools?

A basic spring bar tool is recommended. Some watches with drilled lugs or quick-release bars make installation even easier.

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> Source: [Seals Watch Co](seals-watches.com/blogs/journal/how-to-install-size-a-no-pass-parachute-watch-strap-marine-nationale-guide)