Sellers, if you use the correct terminology, you will guide buyers to your products easier.

ZR1 refers to C3 corvettes (with the ZR1 option ordered) built during 1970, 1971, & 1972  Only 53 were built during this time. Not all 70-72 Corvettes were ZR1s. All ZR1s had LT1 engines but not all LT1s were ZR1s. There was also a ZR2 option available only in 1971, these were {LS6 engine} big block 454 engines. Only 12 of these were produced, hence not all LS6s were ZR2s.

ZR1 also refers to the C6 Corvettes (with the ZR1 package) model year 2009 and up. Again, not all 2009 and up Corvettes are ZR1s and there is a BIG difference between the Z51, Z06, and ZR1 packages.

ZR-1 refers ONLY to C4 Corvettes (with the ZR-1 package/option) built from 1990 through 1995. Not all Corvettes built during this period were ZR-1s. Again ... there is a major difference in ZR-1s, Z51s, and Z07s.