Conn Vintage One Trumpet Accessory KitThis accessory kit made for Conn's Bb trumpet Vintage One model gives you the opportunity to switch your tuning slide or add heavy weight caps. The caps can be used on a Bach Stradivarius since it's the same threads. This accessory kit made for Conn's Bb trumpet Vintage One model gives you the opportunity to switch your tuning slide or add heavy weight caps. The caps can be used on a Bach Stradivarius since it's the same threads.