Make sure the drum have been screwed tightly, drum mandrels with self-expanding rubber cushion, making the sanding bands close to the manderl firmly and acheiving better finishing Commonest and standard size drum sander set which are widely applied in smoothing and curved edges, polishing both soft and hard materials, like home improvement, artwork, woodworks and other finishing and working Note: please wear professional glasses to protect your eyes, because maybe there are flying grits when the sanding drum turning at high speed Steel copper sand wool abrasive sleeve is more and wear-resisting Suitable for polishing on metal, model, wood sculpture, root sculpture, Manufacturer: Limtula