Studio-98 Extra Large Size Set of 3 Grey White Black Cards 4 inch x 5 inch 18% Gray White Balance Card for Digital and Film Photography Color Correction Light Block with Lanyard 18 % Grey Card for DSLR, Video, Film and Photography Color Calibration. Each Card is 4" x 5", Extra Large Size for This Type of Cards (Compared with 2" x 3"). Same Color on Both Surfaces. Made of Flexible PE board. Waterproof. Easy to Store and Carry with Lanyard. Works with Light Meter or Digital Camera.