Rupps Drums Shop Main Shop > Hardware > Pearl Hardware > Pearl Parts And Accessories Pearl Mask for BT3 GK90 Click for larger imageSKU Number: GK90 MSRP: $9.00 You Save:$0.00 FREE Tech Support FREE Lifetime Warranty Rupps Price: $9.00 Quantity: Pearl GK90 Mask for BT3. Hide hole of the BT3