Matthew Stelzer 2021 “Back To Back” T-shirt. Kicking off the new season with brand new gear from your defending two time Knoxville Raceway Pro Sprint Champion Matthew Stelzer and his No. 99 speed machine. This designs features the brand new scheme for the No. 99 along with paying recognition to his victories in 2019 & 2020. This R&R Enterprises Design is printed on a black Gildan 8000 light weight tee.