Ezy Storage 75L/79.3Qt Waterproof Clear Latch Tote IP-67 FBA34064 - The Home Depot
Ezy Storage 11.4-Liter/12-Quart Waterproof Clear Gasket Tote at Menards®
Ezy Storage 11.4-Liter/12-Quart Waterproof Clear Gasket Tote at Menards®
Amazon.com: Ezy Storage IP67 Rated 50 Liter Waterproof Plastic Storage Tote with Airtight Lid for Kitchen, Bedroom, Garage, Shed, and Bathroom Storage, Clear : Health & Household
50L Waterproof IP67 Storage Box — Ezy Storage
Probably the most space efficient airtight (waterproof) box for 12 spools and some desiccant - "Ezy Storage 32L/33.8qt Waterproof tote". Only about 1/8" space on top remains once lid is closed :