Remove the pickup and other materials from the box.
The BD-1 is designed to fit any double bass bridge. Some bridge slot openings will need to be widened slightly. We recommend 200 grit sandpaper, folding the paper appropriately to make it sturdy. If possible, use a thin piece of plastic or metal plate between the sandpaper. This will help while sanding and keep the sanded surface flat, which is important. Before you start sanding, use appropriately cut cardboard placed around the bridge to protect the varnish of the instrument. Widen the slot slowly, stopping frequently to try attaching the pickup sensor. This will avoid making the slot too wide.