This is the Novak 2S Super-PowerCap Module.

FEATURES: Replacement power capacitor module for the Novak Pulse brushless
            racing ESC, and an upgrade for the Novak Havoc Pro ESC and Impact
            ESCs
          Also may be used with any other brushless ESCs that electronically
            advance motor timing and operate on 2S LiPo or 4-6 cell NiMH
            batteries
          Improves efficiency, lowers ESC operating temperatures, and
            suppresses dangerous voltages generated by increased motor RPM in
            timing advance brushless ESCs
          Factory-wired with 16GA silicone wire with pretinned leads
          Novak-developed suppression and clamping circuitry and components

INCLUDES: Novak 2S Super-PowerCap Module with 16GA Wire Leads

SPECS:    Approximate Length: 1.4" (36mm) including shrink wrap (not including
            wire leads)
          Diameter: 0.79" (20mm)