What is the bushing like item clamped onto the center of these ITR axles?

I bought some reman'd GSR axles recently and they do not have them. Wondering if they are important.

 

It's a vibration dampener, they come stock on most/all axles. Most people don't notice a difference in axle life without the dampener, but I'm very **** about retaining them.

I've had the same set of OEM axles for the last four years, and I have a local rebuilder rebuild the joints and leave the shafts alone - a number of the quick rip Pep/Advance/etc parts store carry aftermarket axles with poor QC, that have had their shafts overhardened and are prone to coming apart at low power levels.

 

well alrighty then. Thank you

 

uNF

I feel constrianed to point out, however, that a lot of the quick rip's aftermakret axle shafts are good. RLZ reported having a set last a good while on slicks at 500 whp power levels - surprised the **** out of them - but after having an axle in a stock 90 crank hp Mazda 323 come apart like a greenstick fracture, and one in a 91 DX beater break off at the spline, I feel the need to point out that the QC checks involved in them is very poor.

 

those bastards are only extra weight!
every ounce counts.