[turf3]

Looks like brass, not Rulon.

It's not clear what the issue is that you're trying to solve but if you find yourself trying to lift the horn with your right thumb, shorten the strap. Period.

 

[turf3]

Not raising the strap hook; shorten the strap. With the horn hanging from the strap, 100 percent of its weight on the strap, you should adjust the strap's length, angle of neck, angle of mouthpiece so that the mouthpiece just enters your mouth while you're standing or sitting erect, wtihout ducking your head or trying to lift the thing with your right thumb. The ONLY forces exerted by your two thumbs should be light "steering" forces to guide the thing to you.

 

[turf3]

What’s a “Rulon”?

If this is a question about thumb hooks, then the answer is that these have been around for some time in various forms.

Rulon is the trade name for a family of PTFE plastics produced by Saint-Gobain Performance Plastics. Rulon plastics are known for their low coefficient of friction, excellent abrasion resistance, wide range of operating temperatures, and chemical inertness. Common applications for Rulon include seals, piston rings, bearings, and electrical insulation.[

- Wikipedia

 

[turf3]

There shouldn't BE any tension in the interaction of thumb hook and thumb, for alto tenor baritone bass and curved soprano saxes. The strap should carry 100% of the weight.