This item will be cut from .187" (4.6mm) Raw Aluminum.
You will need: 4x 3/8in by 1" Bolts - 8x washers - 4 nuts to secure the box to the bracket, 4x Lock'N Ride Plugs, and 1x Box of your choice. (See Amazon Links Below)
The bracket will accommodate a box no longer then 33 in wide to allow room to use the lock'N Ride Mount. The raised bracket is intended for a 31x8x8" box. The raised bracket gives you about 8-9" of space under the box for storage. The Flat bracket is intended for a 30x11x10" box.
Confirmed Fitment: 2020 S900
Fits Polaris Part# (Polaris 2637552 OEM Black Rear Box Assembly) Replaces Previous Part Number(s): 5451115-070, 5451115, 2636779, 2635463-070
Box In Photo: Carpartsinnovate 31"x 9" Truck Pick-up Black Aluminum Tool Box w/Handle & Lock Trailer Storage
https://www.amazon.com/Carpartsinnovate-Pick-up-Al...
Lock'N Ride Mounts: GripPRO ATV Anchors to fit Polaris Lock & Ride ATV Tie Down Anchors Made to fit RZR, Sportsman
https://www.amazon.com/Polaris-Lock-ATV-Anchors-Sp...