buzz For Yamaha Trumpet Water Key Screw GP ■ Unused ■ Gold-plated finish ■ Brass Improves sound cohesion by increasing airtightness. Because of the emphasis on airtightness, installation may be difficult in some cases, but applying grease to the screw threads will allow for smooth installation. ＜About Shipping＞ ■ Nekopos (shipping costs covered by the seller) ■ Ships within 1-2 business days after payment confirmation ■ Shipping-related compensation is based on the prescribed rules of the shipping method.