Food-grade silicon caps designed to seal exposed tri-clove fittings. We are using them as go/no-go system.
After any fitting/hose/gauge/pump has been cleaned, we hit it with some ethanol-based sanitiser then the cap gets applied.
This will prevent dust, mould, bugs etc, from contaminating the fitting.
Sold in quantities of 25 per pack at $25 ($1 per unit)