Mirka pad saver discs are an excellent idea to extend the life of the backing pad on your random orbit sander. The multi-hole configuration on the 150mm version allows fitting to many different makes of sander. They are fitted between the sanding pad and the abrasive disc minimising wear of the sanding pad, simply peel off and discard when it eventually becomes worn. When using Abranet® abrasive discs with many random orbit sanders, a more positive attachment to the sanding pad can be obtained with the use of these discs. 77mm, 125mm and 150mm diameters with hook and loop backing are available. N.B. The hole pattern of the 125mm and 77mm pad savers are designed to fit Mirka sanders but could be adapted for other makes if required.