An adjustable pallet or carrier for a sterilisation system comprising a platform (42) configured to provide support for products to be sterilised and an adjustment mechanism (46) configured to vary a length of the platform in the intended direction of travel of the carrier. The mechanism may be manually adjusted or comprise a drive interface for powered adjustment of the carrier. The platform may comprise detents to fix the platform at predetermined spacing. The carrier may include vertical walls (38, 40) extending from the platform； the platform itself may comprise a front and rear section (44). The carrier may be adapted to travel along or engage with a conveyance arrangement, such as by support from underneath or by mounting arrangements allowing the carrier to be suspended. The carrier adjustment mechanism may be configured to move the front and rear sections by equal amounts with respect to the centre of the carrier, such mechanism including a rotary input, such as a worm drive. The conveyance arrangement may comprise a number of adjustable carriers.
