The Mirka 24-38P-400 Iridium 2.75 x 15.75 Grip 140H Perf 400 Sandpaper Sheets are perforated abrasive sheets sold in a 50-pack for fine sanding work. This is a sandpaper sheet designed for fine surface sanding and finish prep. Model Number: 24-38P-400. If you run a sander that uses this 2.75 x 15.75 inch grip-backed, 140-hole sheet format, this is the kind of consumable that matters because fit, hole pattern, and grit all affect finish quality and dust collection performance.

The key spec here is the combination of 400 grit, grip backing, and a 140-hole perforation pattern. The 400 grit rating puts this sheet in the fine-sanding range, where the goal is not aggressive stock removal but leveling, refining, and getting a surface ready for the next stage. The grip backing matters because it is built for quick attachment and removal on compatible hook-and-loop style sanding pads. The 140-hole pattern matters because it is meant to line up with matching dust extraction systems, which can help reduce loading and keep the abrasive cutting more consistently.

Mirka's Iridium line is widely recognized for sanding applications where finish quality and consistency matter. Even with limited source data, the product naming tells you what you need to know to avoid ordering the wrong sheet: size, backing type, hole count, and grit are all spelled out. That is important with sanding abrasives because a sheet that is close in size but wrong in length, hole pattern, or attachment style can be useless on the machine you own.

This product is sold as a pack of 50 sheets, which makes more sense for users who go through abrasives regularly rather than somebody buying one or two sheets for a one-off repair. A larger pack helps keep the exact same grit and sheet pattern on hand, which is useful when you want predictable finish results from start to finish on repeat work.

From a practical jobsite and shop standpoint, the perforated format is the detail worth paying attention to. On a compatible sander, the hole pattern supports airflow through the pad, which is what helps move dust away from the work surface. That usually means less clogging, cleaner sanding, and less wasted time changing loaded sheets before they are truly spent.

This Mirka abrasive is best for users who already know their machine takes a 2.75 x 15.75 inch grip sheet with 140 holes and who need a fine-grit sanding sheet in quantity. It makes the most sense for finish sanding workflows, prep between stages, and other jobs where surface quality matters more than fast material removal. If your priority is coarse stock removal, this is the wrong grit. If your priority is controlled, finer sanding with a specific sheet format, this is the right kind of product to look at.

Mirka 24-38P-400 Iridium Sandpaper Sheets Keep the Decision Simple

If you already run this sheet size and hole pattern, this is the kind of abrasive that makes sense: fine grit, grip-backed, and sold in a real working pack instead of a token handful.

• Who it's for: Users who need 400 grit sanding sheets for compatible strip sanders or sanding systems that take 2.75 x 15.75 inch, 140-hole grip sheets.
• Why it stands out: The format is clearly defined, the 140-hole pattern supports dust extraction on matching pads, and the 50-pack is a practical quantity for repeat work.
• Worth knowing: With abrasives, fit is everything. Check your machine's sheet size, hole pattern, and backing style before ordering, because close is not good enough here.

• What grit is this Mirka Iridium sheet? It is 400 grit.
• What size is the sheet? The sheet size is 2.75 x 15.75 inches.
• Does it use a perforated hole pattern? Yes. It uses a 140-hole perforated pattern.
• How many sheets come in a pack? The package quantity is 50 sheets.