Will these struts stop my garage door from sagging?

They add horizontal rigidity to a door section, which helps with mild sag and flex. If the door is badly bent or the hinges and rollers are worn, fix those first.

Are 22-gauge struts strong enough for a double-car door?

For a standard double door, many installers prefer 20- or 18-gauge struts. 22 gauge is best for lighter single doors or light reinforcement.

Do the struts come with screws or bolts?

No. The bundle is struts only, so you supply the self-tapping screws or bolts and washers for your door.

How do I attach them to the door?

They mount horizontally on the inside face of a section, screwed through the strut into the door's stiles. Place them where the door flexes most, usually the top section.

Can I cut a 16-foot strut to fit?

Yes, 22-gauge steel cuts with tin snips or a hacksaw. Cut ends should be deburred so they don't catch on the door or your hands.

What do the wire size and spring length specs mean?

Those figures describe the torsion spring the struts are paired with, not the struts themselves. Match them to your existing spring if you are replacing a spring at the same time.