Blizzow Desk Book Stand Holders for Reading Hands Free, Durable Metal Adjustable Book Stand, Sturdy Lightweight Foldable Portable Bookstand -Cookbook, Recipe, Tablet, Music Book, Documents (White) White electronics3 the button hole is at

the button hole is at bottom of case

Our sound meter can read between 30dBA~130dBa

the output current can be 15mA around

NATO standard U94 body - Alligator clip for attaching to clothing or MOLLE webbing

Blizzow Desk Book Stand Holders for Reading Hands Free, Durable Metal Adjustable Book Stand, Sturdy Lightweight Foldable Portable Bookstand -Cookbook, Recipe, Tablet, Music Book, Documents (White) White electronics3 the button hole is atBlizzow Desk Book Stand Holders for Reading Hands Free, Durable Metal Adjustable Book Stand, Sturdy Lightweight Foldable Portable Bookstand Cookbook, Recipe, Tablet, Music Book, Documents (White) Adjustable Metal Reading Rest Tablet Study Room Book Holder Foldable Cookbook Stand Feature: Hands free and no assembly required, make you enjoy learning or working. The reading book holder can be adjusted at multiple angles, to prevent children from myopia.