The Dewalt DT70757 Mixed Drill Bit Set is supplied in a Tough Case This is part of a connectable case system that is TSTAK compatible. Individual Tough cases can be clipped together for easy transportation. This set comes in the Medium ToughCase� ready to fix to the top of your existing Tstak case/tough case system. The DEWALT ToughCase+ Accessory Storage solutions have premium features to help keep drilling and fastening bits organized. The system includes four container sizes; the Small Bulk Storage Container, Small ToughCase�+ Container, Medium ToughCase�+ Container, and Large ToughCase�+ Container for unlimited configurations. The ToughCase�+ Containers feature newly-designed bit storage, with a unique bit bar position that allows for easy removal of bits. Clear lids let users see what's in the case at a glance. In addition, the Small, Medium and Large ToughCase�+ Containers include a proprietary latch system to connect to each other for optimized storage space.