Removed the backseat and vacuumed under the seat.
Found the spare missing seat belt which is good!
Was amazed by the amount of sand, dirt, old tissues etc now under the backseat is like new again!
The good old Dyson vacuum did the trick!
Removing and refitting the backseat is so easy in the 300SE two orange metal clips pull up at the same seat comes out.
Simply place the back seat swab back down make sure it square pushed down the orange clips and you hear a 'click', job done.
Here's a good tip check under your backseat and see if it needs a good vacuum?
I never even thought of removing and cleaning under the backseat in preparation for the Concourse.