Used for recessed mounting of the V2707 Pendant Sprinkler Head (sold separately), the assembly allows for up to 19mm adjustment in the recessing of the sprinkler head. SHFSUV27EA Victaulic Standard Upright Sprinkler Head Victaulic Standard Sidewall Sprinkler Head Victaulic Standard Pendant Sprinkler Head Victaulic Concealed Sprinkler Head