An apparatus for use with negative pressure, comprising: a clamping structure (2000, 4000, 7000) having a first end, a second end, a length extending from the first end and the second end, a width transverse to the length extending along a central transverse axis of the clamping structure (2000, 4000, 7000), and a height transverse to the length and the width, wherein the length and width are greater than the height, the clamping structure (2000, 4000, 7000) comprising: a first side and a second side extending the length of the clamping structure (2000, 4000, 7000) from the first end to the second end in substantially parallel fashion wherein the first side is opposite the second side; a plurality of elongate strips (2301, 2302) extending the length of the clamping structure (2000, 4000, 7000) from the first end to the second end, wherein the plurality of elongate strips (2301, 2302) comprise two outermost elongate strips (2301, 2302) defining the first side and the second side; a plurality of intervening members connecting the plurality of elongate strips (2301, 2302), wherein the plurality of intervening members are configured to pivot relative to the strips (2301, 2302) to allow the plurality of elongate strips (2301, 2302) to collapse relative to one another; and a plurality of cells provided side-by-side in a horizontal plane parallel to the length and width of the clamping structure (2000, 4000, 7000), each cell defined by a plurality of walls formed by either the elongate strips (2301, 2302) or the intervening members, each cell having a top end and a bottom end with an opening extending through the top and bottom ends; wherein the clamping structure (2000, 4000, 7000) is configured such that, in use, upon collapse of the plurality of cells the curvature of the plurality of elongate strips (2301, 2302) within the horizontal plane increases along the length of the clamping structure (2000, 4000, 7000) and the distance between the first end and the second end decreases. a clamping structure (2000, 4000, 7000) having a first end, a second end, a length extending from the first end and the second end, a width transverse to the length extending along a central transverse axis of the clamping structure (2000, 4000, 7000), and a height transverse to the length and the width, wherein the length and width are greater than the height, the clamping structure (2000, 4000, 7000) comprising: a first side and a second side extending the length of the clamping structure (2000, 4000, 7000) from the first end to the second end in substantially parallel fashion wherein the first side is opposite the second side; a plurality of elongate strips (2301, 2302) extending the length of the clamping structure (2000, 4000, 7000) from the first end to the second end, wherein the plurality of elongate strips (2301, 2302) comprise two outermost elongate strips (2301, 2302) defining the first side and the second side; a plurality of intervening members connecting the plurality of elongate strips (2301, 2302), wherein the plurality of intervening members are configured to pivot relative to the strips (2301, 2302) to allow the plurality of elongate strips (2301, 2302) to collapse relative to one another; and a first side and a second side extending the length of the clamping structure (2000, 4000, 7000) from the first end to the second end in substantially parallel fashion wherein the first side is opposite the second side; a plurality of elongate strips (2301, 2302) extending the length of the clamping structure (2000, 4000, 7000) from the first end to the second end, wherein the plurality of elongate strips (2301, 2302) comprise two outermost elongate strips (2301, 2302) defining the first side and the second side; a plurality of intervening members connecting the plurality of elongate strips (2301, 2302), wherein the plurality of intervening members are configured to pivot relative to the strips (2301, 2302) to allow the plurality of elongate strips (2301, 2302) to collapse relative to one another; and a plurality of cells provided side-by-side in a horizontal plane parallel to the length and width of the clamping structure (2000, 4000, 7000), each cell defined by a plurality of walls formed by either the elongate strips (2301, 2302) or the intervening members, each cell having a top end and a bottom end with an opening extending through the top and bottom ends; wherein the clamping structure (2000, 4000, 7000) is configured such that, in use, upon collapse of the plurality of cells the curvature of the plurality of elongate strips (2301, 2302) within the horizontal plane increases along the length of the clamping structure (2000, 4000, 7000) and the distance between the first end and the second end decreases.