The Ready Rails static rail kit for 1U Systems, including Power Edge R210, R310, R410, and R415, provides tool-less support for 4-post racks with square or unthreaded round mounting holes including all generations of Dell racks. It also supports tooled mounting in 4-post threaded racks & 2-post (Telco) racks for added versatility. The static rails support a wider variety of racks than the sliding rails but do not support serviceability in the rack & are thus not compatible with the CMA. This product has been tested & validated on Dell systems. It is supported by Dell Technical Support when used with a Dell system. Designed For Power Edge R320, R330, R420, R420xr, R430, R620, R630; Power Vault DL4000