This hub is required when installing a 2016-2019 CTSV Lt4 Blower or 2017-2020 ZL1 Blower onto a 2014-2018 Truck L83,L86. 

Note: ZL1 Blower lid hits the firewall and is not recommended unless your ok with body/firewall modifications.

Requires - 

https://lsa-conversion-store.myshopify.com/collections/6-rib-pulleys/products/1-adm-2-75-6-rib-lsa-lt4-supercharger-pulley

or

https://lsa-conversion-store.myshopify.com/collections/6-rib-pulleys/products/1-adm-2-50-6-rib-lsa-lt4-supercharger-pulley