On long-distance trips like thru hikes, your physical weight can change enough to require a smaller belt size to achieve the desired fit. These are
How To: Remove and Replace Your Hip Belt
Endeavor Removable Hip Belt – Solgaard
Unbound 55L Ultralight Backpack - Hyperlite Mountain Gear
Hyperlite Mountain Gear Elevate 22 Size: M / Color (style): white
Hyperlite Mountain Gear - Waypoint 35 – Geartrade
Ultralight Backpacking Gear by Hyperlite Mountain Gear
Hyperlite Mountain Gear - Unbound 40L – Geartrade
Hyperlite Mountain Gear Unbound (40L) — Tom's Outdoors
VELPEAU Sacroiliac Si Joint Hip Belt for Women and Men -Hip