Moderator EDIT: Deleted for botting.

 

There are good stuff and cheap crap.

If yours look like the same ones as the link u posted, then it looks like some quality stuff!

I have the same kind of spacer on my rear wheels...20mm. Ive taken some very hard turns and hit bumps that could probably have damaged my rims, but the spacers are still holding up. You’ll be fine! Those spacers are pretty strong.

 

There are two different main STYLES of wheel spacers and there are two VARIATIONS for each style.

One style is called "slip-on spacers", they simply slide over the wheel studs and can be easily removed because they are not bolted on. This style REQUIRES longer wheel studs to compensate for the thickness of the wheel spacer, the kit should come with longer studs. Do not use slip on wheel spacers with the existing length studs, you lose lug nut thread engagement and they are very dangerous like that.

The second style and the PREFERRED type is called "bolt-on spacers", they look like a spacer that already has wheel studs coming out of it. They bolt to the existing wheel studs with their own low profile nuts and the tire/wheel is then attached using your existing lugnuts to the new studs on the spacer.

Both of these spacers is available with the variation of being either "hub-centric" or "lug-centric". Basically this is a little extra "ring" on the inside edge of the spacer (sometimes permanently installed, sometimes it's a removable piece) and on most wheels (except trucks where the 4WD hub protrudes through the middle of the wheel) they are required. It makes it so if the wheel was subjected to a big impact (deep potholes is a great example) the force is distributed onto the hub and not just the wheel studs.

The G35 is designed as hub-centric, the OEM style has a ring around the hub that engages the wheel and almost every brand of wheel spacer will be hubcentric. There's a lot of myth and misconception about hub-centric being BETTER but this only applies if there is actually something on the wheel that attaches to the hub. Our wheels are designed to carry the load hub-centric so it would be better for this application. Not all vehicles are hubcentric though.

The only real down side to running wheel spacers is the extra wear it puts on the wheel bearings. Here's the perfect analogy to describe the extra force. Pick up a dumbbell and hold it close to your body, pretty easy to hold in this position yeah? Now extend your arm with that same weight and hold it out away from your body, that's a LOT harder. Exactly the same as putting wheel spacers on your car, the wheel bearing wears out quicker.

The second downside, and it may or may not be an issue for you, pretty much no tire station in the nation will touch your car if it has wheel spacers. It's a legal liability issue for them so you will typically get turned away, just keep this in mind if you get new tires you will either need to dismount them yourself and drop off just the wheel/tires OR you can remove your spacers before you to go the tire shop.

However I think they're totally worth it, cars look MUCH better with wheel spacers, on my coupe I have 15mm front and 25mm rear.

Quality varies from one manufacturer to the next, wheel spacers is one of those items that I would ONLY buy a reputable name brand.

 

Here's a picture of my fronts, you can see it is hub-centric because of that small raised metal ring at the inside edge. Mine take a special socket with those 4 pins to bolt it down to the existing wheel studs, my OEM lugnuts (and one locking lug) are threaded onto the new studs.