Theres a long list of marine-specific kits well-suited for paddle boarding, but you can also build your own first aid kit with a few essentials
Standout features: Responsive A3 Suspension system that adapts to your body for a custom fit Ventilated back panel 3D AIR hipbelt and shoulder harness eliminates hotspots and pressure points High strength aluminum frame keeps the pack close to your center of gravity Full body U-Zip main opening Sleeping bag compartment Solar panel attachments Removable hydration sleeve converts into an ultralight daypack Pack weight: 5.18 lbs THE DIFFERENCE BETWEEN HIKING BACKPACKS FOR WOMEN VS
At 22L it is sized for a full day with a sensible kit: waterproofs, a layer, lunch and water

360-Degree Reflectivity Bottom Compression Comfortable, Padded Top Grab Handle Daisy-Chain Webbing Offers Lash Points External, Fleece-Lined Pocket For Sunglasses, Phone Or Keys Front Compartment Has Internal Organization With Secure-Zip Pockets And A Padded Tablet Sleeve Large Main Compartment For Books And Binders Protective Dedicated 16'' Laptop Compartment Removable Waist Belt Side Compression Straps Stand-Up Design For Easier Loading And Unloading Sternum Strap With A Whistle Buckle The Luxe Edition Features A Premium, Metallic Embroidered Logo And Metallic Zipper Pulls The Women-Specific FlexVent Suspension System, Certified By The American Chiropractic Association, Has Articulated Shoulder Straps, A Rounded Back Panel, Comfortable Stitch Lines And Soft-Touch Chemise Fabric Two Durable Water Bottle Pockets Can Easily Double As Multi-Use Pockets With Quick-Draw Smartphone Access On One Side U-Pull YKK Zippers Are Easy To Grab Avg Weight: 2 lbs 5 oz (1060 g) Dimensions: 10.8'' x 7.5'' x 18.9'' (27.4 cm x 19.1 cm x 48 cm) Volume: 1831 in (30 liters) Laptop Sleeve: 18'' x 10.6'' (45.7 cm x 26.9 cm)

these usually have a washout as well