These are hardened. RRP's are some other version of the word hardened. These pinions have lasted me years of abuse and still mesh perfectly. I will not buy another pinion gear. Also, as another stated, they are tight, but the newer one's are not as tiread moreght.
VERY hard pinion!
ddd228 - June 27th 2012
I ran these but now I need a longer(wider) gear tooth area. I run a 10mm 58 tooth spur. Dave in Seattle.
Best pinion for the money
Snellemin - January 23rd 2011
I got me the 25T, 28T and 30T. These outlast the Robinson Racing pinion when running metal spurs.
Larry Palmer (crazyjr) - October 05th 2010
Bought 2 (19 and a 20) three years ago, no sign of wear yet. Very smooth on spur, you will not be disappointed
Tat2 - July 18th 2010
These are perhaps the most durable pinions I have used to date. My only complaint, and it is a minor one, is that they fit VERY tightly on my Neu's motor shaft. Good for when you're running the vehicle, not so good when it comes time to change ratios. read moreThey can rust rather easily too. I give 'em a 4 out of 5.
bigboi146 - May 25th 2010
Mike makes the only pinion worth buying. I highly recommend them. (P.S. I've been running one on the same truck for a year with no signs of wear and tear.