3M COMPANY 03148 2-3/4x5 Regular Sand Block

Difficult to lift rubber flap far enough to get sandpaper over spike. End of slot has an angled corner so can't butt end of sandpaper against end of slot. Result is sandpaper is loose on block and not as effective for sanding. It is helpful to be able to butt sandpaper against end of slot so that sides of sandpaper are in-line with sides of sanding block's face. 3M part no. 05519 is easier to load the sandpaper, the end of the slots are straight which helps line up the sandpaper, and the sandpaper is held tightly against the block's face. Possible benefit to 03148 over 05519 is that the top of the 03148 is angled for comfort. Downside to 03148's angled top is that the block is taller and so cannot fit in tight spaces like between a retrofit vinyl window and the drywall sill like the 05519 can. Note that this website shows 2 images for the 05519. One of the images shows the 05519 which is a one-piece rubber block. The other image shows the 03149 which is a wider 2-piece design.