The elastic cord ensures your water bottle stays securely in place. 【Tool-Free Installation】Easily install and remove the bike rear seat bag using five adjustable hook-and-loop straps. Enjoy easy access to your items from either side with the double zipper design. 【Safety and Visibility】Reflective strips enhance night-time riding safety, with straps to secure a tail light for added visibility and protection. Rear Pocket & Reflective Strip Expand the storage capacity with the fold-out extension layer, providing an additional 20L of space. 20L-45L Large Capacity]The standard capacity is 20L and can expand to 45L. It features a main compartment with a removable divider, an expandable layer... Comes with a detachable rain cover to keep your items dry in the rain. 3.15 Inch Gold 60th Birthday Candles for Sisty Years Old Birthday Cake Toppers Wedding Anniversary 60 Candles Bday Decorations (Gold, No. 60) · Unscented Electric Bike Accessories ArcEnCiel Bike Bag Bicycle Panniers Water-Resistant Large Capacity Rack Trunks Rear Seat Carrier Pack - Rain Cover Included Ebike Accessories Coolchange Cycle Rack Bag Large Capacity 35l Bike Cycling Rear Seat Ride safely during dark conditions or at night with the reflective strip. Provides enhanced stability when riding with the expansion layer in use. Fasten the bottom two straps 【20L-45L Large Capacity】The standard capacity is 20L and can expand to 45L. Designed for easy carrying and handling. Customize the interior layout with Velcro dividers to separate and protect different items. 【Versatile Use】This multifunctional bike bag features a top handle and adjustable shoulder strap for easy carrying when not riding. Conveniently secure additional items with the bungee cord. Fits most bike racks, including mountain bikes, road bikes, and e-bikes. The interior is lined with waterproof material to effectively prevent leaks.