A prepackaged mesh unit which comprises a spreadable sheet, a guide rod configured for remotely positioning the spreadable sheet within a body cavity, and a plurality of self-extending elements collapsed with the spreadable sheet and held at one end by the guide rod, wherein the self-extending elements have an elastic property and store elastic energy while collapsed with the spreadable sheet, wherein the number and configuration of the self-extending elements is selected to match a size and shape of the spreadable sheet.