Differences between First and Second Batch RLHs

		First Batch (RLH 1-20)	Second Batch (RLH 21-76)
Date built		Early 1950	Late 1952
Chassis	Type	AEC Regent III 9612E	AEC Regent III 9613E
	Radiator cover	Chrome	Aluminium
	Cab switch and control panels	Simms bank of 6 toggle switches and fuses, next to starter switch. Simms control unit with toggle switches and plunger offside of driver's seat.	Bank of LT style heavy duty switches/ fuses next to starter switch. CAV dynamo control unit only offside of driver's seat.
	Compressor air intake, in cab, below driver's seat	Westinghouse air filter and anti-freezer unit (alcohol reservoir)	Simple LT style felt filter
	Chassis length	26ft 0in	26ft 7⁵⁄₁₆in
	Turning Circle (official)	60ft	57ft
Body	Offside rear corner lower panel	1-piece	2-pieces with horizontal beading between
	'Used Tickets' bin on platform bulkhead	Built into panel	Separate box bolted onto panel, LT style
	Rear direction indicators	None when new. Later, fitted like RM, with separate lamp either side of advert panel	None when new. Later, 'double arrow' fitted into same panel as number plate
	Horn position, hung from canopy above engine	Closer to front of bus	Further back
	Driver's front opening air vent flap below windscreen	Yes	No
	Ventilators on upper deck roof	Yes, 3 each side	No
	Blindbox light fittings	Large circular surrounds	Bare cap holders
	Interior seat frame tops	Chrome	Aluminium
	Saloon lighting	Controlled from cab	Controlled by conductor, under stairs