Made of Spring steel ensuring the head of the saddle stays rigid while allowing the seat flexibility Choose from 6 color coded sizes. Details below are approximate: EASY-CHANGE Gullet Individual Replacement The EASY-CHANGE Gullet System lets you select the optimal tree width for your horse's current shape and muscling. The EASY-CHANGE Gullet Plates are designed to be be completely rigid, ensuring they cannot spread or change shape under normal usage. The individual Gullet Plates are available in six different color coded sizes ranging from Extra Wide to Narrow. Features: Made of Spring steel ensuring the head of the saddle stays rigid while allowing the seat flexibility Choose from 6 color coded sizes: Extra Wide (25.3cm or 10 inches) - White Wide (24.5cm or 9.6 inches) - Red Medium/Wide (23.8 cm or 9.4 inches) - Blue Medium (22.8cm or 8.6 inches) - Black Medium/Narrow (21.8 cm or 8.6 inches) - Green Narrow (21 cm or 8.3 inches) - Yellow Item Specifications: Material: Spring steel