Sparklites have a fixed striking wheel. The flints are held inside the handle by small springs and steel plungers.

With the current plastic service issue, once the flint is used up(remember that means thousands of sparks)that's it. Everything is sealed inside the plastic.

The prototype brass units had a small threaded dial, much like a wristwatch to access the spring and plunger assembly. The test run of aluminum went to a tiny hex thread- hence the wrench. The tiny vial holds standard lighter flints.

This is something Oak wants to produce for the civilian market.
It's a matter of enough market interest, which we may help?