Aluminum oxide is a very hard mineral that maintains sharp points on the grains much longer than natural abrasives such as emery or garnet. The abrasive grains are adhered to the sandpaper with some space between them, known as open-coat construction, to minimize the buildup of dust on the surface of the paper, which would otherwise load the abrasive points. Loading often results from sanding soft materials and can clog the abrasive, shortening the usable life of the sandpaper sheet.
3M 02117, Paper Sheet 346U, 50 D-weight, 9 in x 11 in, 7000120222
$1.29
Factory Stock, 7-10 Day Leadtime
3M Paper Sheet 346U is constructed of aluminum oxide and comes in a range of grades and sizes to accommodate many different projects. The paper backing is durable for coarse sanding, yet flexible enough to be used on curved surfaces. Its cut-rate and durability make this an excellent choice for blending the joints of connecting pieces in wood- and metal-working.

3M 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
3M 21543, Scotch-Brite Roloc Clean and Strip XT Pro Extra Cut Disc, TR, 2 in x NH, A XCS, 7100179815, 60/box
3M 22394, Roloc Disc 361F, 50 YF-weight, TR, 3 in, Die R300V, 7000045096
3M 45714, Cubitron II Hookit Cloth Disc 947A, 120+ X-weight, 3 in x NH, D/F 3HL, Die 300BE, 7100113113
3M 86745, Diamond Disc, 2" Roloc, 674W, 120 Mesh, TR, 7100022116, Box of 10
3M 22393, Roloc Disc 361F, 36 YF-weight, TR, 3 in, Die R300V, 7000045093
3M 22392, Roloc Disc 361F, 24 YF-weight, TR, 3 in, Die R300V, 7000045090
3M 05043, Cloth Belt 384F, 80+ XF-weight, 1/2 in x 12 in, Fabri-lok, Full-flex, 7100141435, 200 per case
3M 05526, Wetordry Sponge Pad 20, 5-1/2 x 2-3/4 in x 3/8 in, 7000045663
3M 66630, Cloth Belt 341D, 50 X-weight, 6 in x 48 in, Film-lok, Single-flex, 7000118864, 20 per case
3M 03051, Sanding and Finishing Disc Holder, 03051ES, 2 inch, 7010364781
3M 34556, Cubitron II Net Sheet Roll, 320+, 80 mm x 10 m, 7100283765, 6 Rolls/Case, (Previously Item# 7100247340)
Standard Abrasives 722809, PSA A/O Extra Disc, 5 in x NH, 60, 7010368721
3M 28719, Wheel Adapter Kit 28719, 1 in x 5/8-11 Internal, 7100050705
3M 22405, Roloc Disc 361F, P100 YF-weight, TR, 3 in, Die R300V, 7000045102
3M 34566, Cubitron II Net Sheet Roll, 240+, 70 mm x 10 m, 7100247511, 6 Rolls/Case
3M 30190, Trizact Hookit Foam Sheet, 2-3/4 in x 5-1/2 in (70 mm x 140 mm), 3000 grade, 7100072763, 5 sheets per pack 
