The Modular Kit includes a Modular Suspension with Connbox, a complete basket Modular windshield (covers the mic completely) & removable fur cover Windjammer. This gives you a very versatile solution that can be boomed or hand held, and the industry standard shock mount & windshield combo kit.
The BBG windshield & Windjammer, is a windshield solution only (no suspension), and uses the same windshield structure & material as the Modular, but only covers the front portion of the mic. The rear of the microphone will be exposed to wind buffeting. You’d still need a shock mount, like the INV 7 HG MkIII.