This offer provides Windows Server 1803-based Stemcell for Tanzu Application Service for Windows product. A BOSH stemcell is a versioned operating system image. The Windows VM with security updates serves as the base for all future stemcells produced from clones of that base VM. This enables you to build new stemcells without having to run Windows updates from scratch each time. You can also use a “snapshot” feature to maintain an updated Windows image that does not contain the BOSH dependencies.