Sinn – On The Fly Extension Link Installation Guide

Tools Required

• The hex key supplied with your Sinn watch (for hex bolts)
• Push-pin or spring-bar tool
• (Optional) Purple Loctite 222 low-strength threadlocker — may help secure the screw, but avoid excess as it can make future removal difficult.

Installation Steps

1. Remove the clasp from the bracelet

   
   
   • Use a push-pin or spring-bar tool to depress the spring bar that connects the clasp to the bracelet.

   • Detach the clasp completely.

     
     

2. Remove the original diver’s extension

   
   
   • The Sinn diver’s extension is held in place by hex bolts.
   • Using your Sinn-supplied hex key, remove the bolts securing it to the bracelet.

   • Retain the original bolts — they will be used to install your On The Fly link.

     
     

3. Install the Steel Reef On The Fly Extension Link

   
   
   • Position the extension link where the diver’s extension was removed.
   • Using your original Sinn hex bolts, secure it in place with the hex key.

   • (Optional) Apply a very small drop of Loctite 222 to the bolt threads before tightening.

     
     

4. Reattach the clasp

   
   
   • With the extension link in the open position, slide the clasp’s connector into the extension link’s folding arms.
   • Use the spring-bar tool to depress the spring bar and secure the clasp back onto the bracelet.

About Bracelet Fit

• The OTF replaces the Sinn diver’s extension, which is designed for wetsuit use and not daily micro-adjustment.
• You may need to adjust your bracelet attachment point along the clasp’s micro-adjustment holes to achieve your perfect fit.