The DrayTek rack mounting bracket part number DR101 is an accessory item used rack mount most DrayTek dual WAN routers into a data communications rack.
It is 1 RU in height and will suit data cabinets with 19 inch rails.

Most DrayTek dual WAN have a slot on each side of the housing as shown in the diagram below  which simply slides into the cut out of the rack mount bracket.

 

 

To mount the router into the rack mount bracket you just have to align the slots in the router with the bracket as shown here then drop the router into the cut-out in the bracket.

 

Once the routers are placed into the rack mount bracket the assembly will look like this.

All the routers that can be mounted into the rack mount bracket use a similar housing design with the same dimensions and slots in the housing.
Listed below are the router models that can be used with the DR101.
On the left are the current router models and includes the Vigor2927, 2866 and 2865 series.
In the right column are the older model routers that can also be used with the DR101