How to Use: 1: Take out the product and connect the pre‑prepared for Nikon camera. 2: After installation, it can be used after installing the adapter ring as required. Specificatio Item Type: Macro Ring Flash Material: Plastic Color: Black Weight: Approx. 820g / 28.9oz Circuit Design: Automatic Insulation Two-Stage Crystal Guide Number: GN14 (ISO 100) Flash Structure: Two Groups of Lamps Flashed Together or Group A And Group B Flashed Alone Flash Time: 1/200s-1/20000s Number of Flashes: 100-1500 Flashes Flash Coverage Area: About 80° up and down / About 80° Left and Right Flash Mode: Auto Mode TTL / Manual Mode M / Strobe Mode Multi Flash Ratio Control: Adjust Between 1:8~1:1~8:1 in 1/2 Step Increments External Interface: Hot Shoe, PC Synchronization Socket, External Power Interface Transmission Range: 20cm-5m / 7.9in-16.4ft Recycling Time: About 2.9 Seconds Additional Functions: Power Saving, Overheating Protection Exposure Control Type: TTL, Manual Flash, Multiple Flash Power Supply: 4 AA Batteries (Delivered Without Batteries) Applicable Models: For D7100, D7000, D5200, D5000, D3200, D3100, D90, D300S, D600, etc. Package List: 1 x Ring Light 1 x Mini Base 1 x Manual 8 x Adapter Ring 1 x Storage Bag