Sometimes analyzing your air directly from the Scuba valve can be a bit tedious. High pressure air is not as manageable as is low pressure air from your BCD inflator hose. The Analox BCD Flow Restrictor helps reduce air flow to manageable level allowing you to analyze your gas percentages easily. Designed for use with an Analox analyzer, this lightweight and durable restrictor is made from durable plastic and corrosion resistant metal for low maintenance. Restrictor hose easily attaches to the regulator inflator hose and barb fitting attached to the Analox O2EII Pro Analyzer (see SKU's: AQUN02E2P and AQUNAK).