Blum Tandem Premium Undermount Slides Standard Self Closing Full Extension For 15" Drawers 100# Class Full extension for 1/2" & 5/8" drawer side. 15" Drawer requires 15-3/4" Minimum Interior Depth For inset applications increase Minimum Interior Depth by drawer front thickness Undermount to drawer - Side-mount to cabinet, Rear-mount with bracket, Search: Blum Rear Mount Locking devices are required, Search: Blum Locking Device For Tandem Drawer Slides Add smooth and silent closing by trying BLUMOTION, Search: Blum BLUMOTION Insert