of the wafer it is currently most preferred that the wafer contact area of wafer supports 120 122 124 and 126 be minimized as shown so as to minimize friction and dragging against the wafer surface when a wafer is inserted and withdrawn from the carrier other embodiments having a larger contact area however such as is shown in fig4 may also be used the insert as illustrated is preferably injected molded of a rigid and resilient plastic such polycarbonate but may be formed from any suitable and compatible material in the embodiment illustrated in fig2 and 3 recess engaging portions 30 and 32 are located at the side margins or plate 21 and have tab structures which alternate between a high tab 80 and a low tab 82 when installed in a wafer carrier high tabs 80 are in frictional contact with a top surface 86 and low tabs 82 are in frictional contact with bottom surface 88 of recess 53 as best illustrated in fig6 and 7 high tabs 80 and low tabs 82 are placed so as to extend substantially the length of each recess 53 end tabs 90 have frictional surfaces on both the top and bottom also high tabs 80 and low tabs 82 are configured so that when insert 20 is installed in the recesses.