Possible Clues:

• The tiller starts to go on ahead
• The gnarled tree in protective cover
• Man left London police force in this?
• Police hat
• Sounds as if the hot place is encountered with one of the overheads
• Protection for a Rollerblader
• Gear for a football player
• Tree in the developed cover
• Protective head-covering for armour or motor cyclist
• Protective covering for head of motor-cyclist