The position of the tray is then secured with a fastener screwably extending through the second arm into {HEAD ~ a friction fit relationship} with {TAIL ~ the shelf} 
The position of the tray is then secured with a fastener screwably extending through the second arm into { HEAD ~ a friction fit relationship } with { TAIL ~ the shelf }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL