The apparatus 1, wherein said biasing means each comprise at least one torsion spring for biasing {TAIL ~ the respective attached flap} outwardly into {HEAD ~ its extended position} 
The apparatus 1 , wherein said biasing means each comprise at least one torsion spring for biasing { TAIL ~ the respective attached flap } outwardly into { HEAD ~ its extended position }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD