PSA stands for Pressure Delicate Adhesive. They're self-adhesive sanding discs that quickly and easily connect to your sanding machine. Available in both fabric backing or paper backing with fabric being used for weighty responsibility grinding and paper remaining a more very affordable and lightweight option for lighter sanding/finishing. Make sure https://www.facebook.com/permalink.php?story_fbid=pfbid0FmPB9VyPFjcaqb4oz9WZuNVvss32VZKiwQpAxv7dDnQVFD3TR9akZ7GUUPGgiMHEl&id=61562415773754&__cft__[0]=AZVFQVZT8nrsTkNpKWlf_yjsFg2R8lgV-g_l7GuTm3e8SlQMQc0J7okK5g8ZySPX2dLZ1N4QNRCnjFz-HVemGmoROEWRd0ppsT9SF28aLadA431kKoFDOvj4rLxOakB1JUDzPDMM5BAMNTjLy1EZ8tV9r40hp2gaxEMZ6ulKtcjloR_Zzy0xzEwBU-84aZ4VOqPfPNSNmL_8-Bu2pUFqAQNw&__tn__=%2CO%2CP-R