Umpqua Northfork Sling Pack Yellow Dog Flyfishing Umpqua Northfork Sling Pack Yellow Dog Flyfishing UMPQUA Northfork Pine Sling Pack (35298) eBay Umpqua Northfork Sling Pack TCO Fly Shop Umpqua Northfork Sling pack Gunnison River Fly Shop. Designed for your Best Day on the Water. The NorthforkSling Pack features pockets for fly boxes, leader & tippet, indicators, and more. Everything you need for a comfortable and productive day on the water. Spacious Main Compartment: Holds up to 4 full sized fly boxes. Secondary Compartment: Accommodates 2 full sized fly boxes. Internal Pockets: Organize leaders, tippet, indicators, and more. Net Slot: Easy access slot for your fishing net. External Fly Patch: For quick access and fly drying. Water Bottle Pocket: Holds a water bottle securely. Additional Stretch Pockets: Easy access storage options. Proprietary VersiLoop Accessory Attachments: Compatible with Umpqua's 6pc accessory line. Two Adjustable Web Straps: For rod attachment.