Product specification:

Model: UM-865
Type: Undermount, Double Bowl
Material: 304 Stainless Steel
Processed: Brushed
Thickness: 18 Gauge/1.2mm
Size: 16¹/₈"x18"x7"
        3-1/2" (114mm) drain opening
        3-1/2" (114mm) to 1-1/2" (32mm) strainer
Comes with mounting template, easy to install.

Option:strainer $12/each
Option:grid $60/set