Dimensions in mm (1 mm = 0.03937 inch)
Threads in inches (1 inch = 25.4 mm)

All dimensions in mm (1 inch = 25.4 mm). Threads in inches (UNF standard).

• 7/16″ Series Thread: 7/16″-20 UNF-2A Overall Length: 19.05 mm Hex Size: Suitable for standard 7/16″ tools
• 1/2″ Series Thread: 1/2″-20 UNF-2A Overall Length: 20 mm Hex Size: Standard 1/2″
• 5/8″ Series Thread: 5/8″-18 UNF-2A Overall Length: 25.01 mm
• 3/4″ Series Thread: 3/4″-16 UNF-2A Overall Length: 34.9 mm
• 7/8″ Series Thread: 7/8″-14 UNF-1A Overall Length: 35 mm Dual O-Ring design (2-019 & 2-022) for maximum sealing reliability

HYSF underwater blank plugs are precision-engineered dummy connectors designed to protect open bulkhead connectors from seawater ingress, dirt, and pressure damage during storage, transport, or when not in use. Manufactured with premium stainless steel and POM components, these blanking plugs deliver unmatched durability and reliability for ROV, AUV, offshore oil & gas, oceanographic research, and renewable energy applications.

Fully customizable – choose single or double O-ring configuration, extended thread lengths, titanium construction, or exact Subconn® dimensional matching. Contact HYSF for OEM solutions and fast prototyping.