What is the trombone diameter of Hillman 665?

525mm. According to sierman's trombone introduction, the diameter of model 665 of this product is 525mm. Gillman Musical Instrument was founded on 20 1 1, adhering to strict quality and excellent craftsmanship, perfectly integrating international cutting-edge technology, professional design and skillful craftsmanship, presenting original products with ingenious craftsmanship, and producing high-quality and cost-effective musical instruments.