I'm only able to find one mention of sleep masks in the linked study: >In contrast, other practical solutions, such as sending >“sleep kits” containing an eye

I'm only able to find one mention of sleep masks in the linked study: >In contrast, other practical solutions, such as sending >“sleep kits” containing an eye >mask or earplugs and other supplies to servicemembers in >deployed settings may represent >more practical and feasible strategies to encourage healthy >sleep behaviors I wouldn't call this "military-approved," though I use a sleep mask every night.