Start by matching the hood’s mm size to your HERO4 setup and housing. Check that it fits without blocking the lens, ports, or any mounted accessories, and decide if you mainly need sun glare reduction or splash protection. Confirm compatibility with the HERO4 and your existing attachments, and consider the typical filming conditions you expect to encounter.

The rubber material and its thickness are the most important factors for performance. A mid grade hardness offers a good balance between flexibility and durability, while too soft rubber may deform and too thick rubber can add bulk. Thickness also affects how well the hood seals against splashes and dust and how comfortable it is to grip. Look for natural rubber with good wear resistance and minimal stretching over time.

Beginner shooters should prioritize a light, easy to attach hood that does not complicate handling or lens visibility. Professionals may prefer a tougher design with reliable grip in wet or dusty environments and a secure mount. In both cases, ensure the size in millimeters matches your setup and that the hood does not interfere with filters or mounting points.

Mount the hood so it clears the housing latches and avoids contact with moving parts. Clean the rubber with mild soap and water, dry it thoroughly, and inspect for cracks or stiffening, replacing when needed. Avoid harsh solvents that can degrade the material and store the hood away from heat to extend its life.

Verify compatibility with the GoPro Hero4 and any existing accessories, and choose a reputable brand known for action camera gear such as GoPro official accessories, ULANZI, or SmallRig. Look for clear sizing in millimeters, a durable rubber material, and a straightforward mounting design. Consider the return policy and reviews to gauge real world performance.