Case fits combos of up to 10 3.5" HDDs, 40 2.5" Drives (HDD or SSD), or 180 M.2 SSDs | The foam has been ingeniously cut to maximize capacity of each drive type! | The 3.5" HDDs, either 0.75" or 1.0" thick, simply fit into the main pocket | The 2.5" Drives (HDD or SSD) utilize a pull-out foam "rack" that holds 4 drives per main pocket | The M.2 SSDs utilize 2 "flat" bottom foams (for support), and 1 "slotted" top foam to fit 18 drives per main pocket. The M.2 slots only fit SSDs that are 22mm wide, and do not fit heat sinks | Pink Anti-Static Foam is utilized to prevent damage and data corruption that can happen from the natural buildup of static electricity. Only trust Pink Anti-Static Foam when it comes to storing delicate electronics! Foam is closed cell so it can be wiped dry if wet, and is non-abrasive, will absorb impacts, and will not deteriorate over time | The exterior case dimensions are 10.50"L x 9.50"W x 6.87"H. Case is 100% waterproof airtight & dustproof. Hard injection molded plastic shell protects from shocks, drops, impacts, and the elements. Padlock holes for added security. Built in pressure relief valve so the case can be opened in any altitude. Perfect for airline checked or carry on baggage.