2026-09-21 · KeXinMaterials Editorial Team
Waterproof Case IP67 vs IP68 Deep-Dive: B2B Marine / Outdoor / Subsea Buyer Guide (2026)
IP67 and IP68 are not interchangeable. IP67 covers 90% of B2B waterproof needs. IP68 only for subsea or sustained pressure. Here is the 2026 detailed B2B buyer guide.
Why Waterproof Cases Are a Special B2B Category
Waterproof cases serve marine, offshore, subsea, and outdoor industrial applications where case failure means equipment loss + operational delay.
Marine deck operations: spray, splash, brief rain exposure. IP65 typically sufficient.
Offshore oil and gas: saltwater spray, weather deck, helicopter cargo. IP67 minimum.
Subsea ROV and diving: continuous water pressure, depth rating. IP68 required.
For B2B buyers, the cost differential between IP65, IP67, and IP68 (typically 5-10% per tier) does not reflect the operational risk differential. Selecting the wrong IP rating risks equipment loss + safety hazard.
IP65, IP67, IP68: What Each Means
IP ratings are defined by IEC 60529. Each digit has specific meaning. B2B buyers should select by deployment, not by maximum spec.
IP65: dust-tight + low-pressure water jets (12.5mm nozzle, 30 kPa). Sufficient for outdoor / weather deck / construction / workshop.
IP67: dust-tight + temporary immersion in 1 metre of water for 30 minutes. Required for offshore deck, marine deck survey, helicopter cargo.
IP68: dust-tight + continuous immersion at 1-3 metres depth for 30+ minutes. Depth specified by manufacturer. Required for subsea ROV, marine research, diving equipment.
IP rating cost differential: IP65 baseline. IP67 +5-10%. IP68 +25-40% (additional sealing, pressure testing, valve).
O-Ring Materials and Design
The O-ring is what seals the case. Material choice depends on deployment.
Silicone O-ring: temperature range -60°C to +200°C. Excellent UV and ozone resistance. Standard for MIL-PRF-GRF tactical cases. Slightly higher cost.
Nitrile (NBR) O-ring: temperature range -40°C to +120°C. Good oil and chemical resistance. Standard for commercial IP67 cases. Cost-effective.
EPDM O-ring: temperature range -50°C to +150°C. Excellent weather and chemical resistance. Used for outdoor / marine applications.
Viton (FKM) O-ring: temperature range -20°C to +200°C. Excellent chemical and high-temperature resistance. Premium for harsh chemical environments.
O-ring compression: 20-30% compression for proper seal. Over-compression damages O-ring. Under-compression allows water ingress.
O-ring groove design: rectangular cross-section, machined or moulded into case. Groove width 1.2-1.5x O-ring cross-section.
Pressure-Equalisation Valve
Pressure-equalisation valve is critical for altitude-change operations. It allows air pressure to equalise between case interior and atmosphere.
Applications: helicopter cargo, mountain operations, aircraft cargo holds, ROV launch / recovery.
Without pressure valve: case may pop open on descent (high to low altitude) or become impossible to open on ascent (low to high altitude).
Automatic valve: Gore-Tex membrane allows air to flow slowly without water ingress. Standard on our IP67 cases.
Manual valve: twist-to-open allows user to equalise pressure before opening. Used for subsea ROV launch where moisture control is critical.
For B2B buyers operating across multiple altitudes (helicopter + ground + shipboard), pressure-equalisation valve is non-optional.
Material Selection for Waterproof Cases
PP copolymer is the workhorse for IP67 / IP68 cases. Glass-filled PP for premium stiffness. PA blends for extreme temperature.
PP copolymer: standard for IP65, IP67, IP68 cases. Good impact resistance, low cost. Wall thickness 3-5mm.
Glass-filled PP (10-30% glass): premium stiffness for IP68 cases. Required for MIL-PRF-GRF load test. Wall thickness 4-6mm.
PA (Nylon) blends: extreme temperature range (-40°C to +80°C). Used for subsea and aerospace applications. Cost USD 4-6/kg.
At KeXinMaterials we run PP copolymer standard for IP65/IP67, glass-filled PP for IP68 + MIL-PRF-GRF cases, PA blends on request for subsea SKUs.
Application-Specific Designs
Waterproof case design varies by application. Match design to deployment.
Marine deck case: 500x350x200mm IP65/IP67. Foam cutouts for surveying equipment, electronics. Salt-spray tested. EPDM O-ring standard.
Offshore oil and gas case: 600x450x250mm IP67. Foam cutouts for instrumentation, cables. Saltwater corrosion-resistant hardware. Pressure-equalisation valve.
ROV launch case: 700x500x300mm IP68. Foam cutouts for ROV tether, manipulator spares, lights. Manual pressure-equalisation valve. Subsea-rated O-ring (Viton or EPDM).
Diving equipment case: 500x400x250mm IP68 100m rated. Foam for regulators, dive computers, accessories. Heavy-duty O-ring. Optional camera port.
Outdoor expedition case: 600x400x250mm IP67 with IP68 upgrade option. Foam for camping, photography, electronics. Pressure-equalisation valve. EPDM O-ring.
MOQ and Pricing
Waterproof cases fall into three pricing tiers.
Tier 1 stock waterproof: 50-100 cases, USD 95-180/unit, 7-15 days production. IP65/IP67 standard.
Tier 2 custom OEM waterproof: 100-300 cases, USD 130-280/unit (case + foam + valve), 7-15 days production.
Tier 3 new mould waterproof: 1,000+ cases amortised, USD 90-220/unit post-amortisation, 60-90 days mould + 30-45 days production. IP68 deep rated.
Why Choose KeXinMaterials for Waterproof Cases
KeXinMaterials operates 60+ injection machines in a 13,000 m² facility since 2014. PP, glass-filled PP, PA blends available. IP65/IP67/IP68 standard range.
Stock waterproof SKUs: 6 sizes from 350x250x150mm to 800x600x350mm. 50-piece MOQ for stock.
Material: PP copolymer (workhorse), glass-filled PP (IP68 premium), PA blends (subsea). O-rings: nitrile standard, EPDM / silicone / Viton on request.
Pressure-equalisation valve: automatic Gore-Tex standard on IP67 cases. Manual valve on request for IP68 subsea.
Certifications: IP65/IP67/IP68 batch test per SKU, MIL-STD-810G drop test per lot, CE / RoHS / REACH for EU export, FDA compatibility statement on request for medical SKUs.
Trade terms: EXW Shenzhen / FOB Shenzhen / FOB Ningbo. No DDP, no EU warehouse, no US warehouse. Every shipment direct from our 13,000 m² Guangdong facility.
Key Takeaways
- IP65 = low-pressure water jet / IP67 = temporary immersion / IP68 = continuous immersion
- O-ring material: silicone / nitrile / EPDM / Viton by deployment
- Pressure-equalisation valve critical for altitude-change operations
- PP copolymer standard / glass-filled PP for IP68 / PA blends for subsea
- Marine deck / offshore / ROV / diving / outdoor — design varies by application
FAQ
What is the difference between IP65, IP67, and IP68?
IP65: dust-tight + low-pressure water jets (12.5mm nozzle, 30 kPa). Sufficient for outdoor / weather deck / construction / workshop. IP67: dust-tight + temporary immersion in 1 metre of water for 30 minutes. Required for offshore deck, marine deck survey, helicopter cargo. IP68: dust-tight + continuous immersion at 1-3 metres depth for 30+ minutes (depth specified by manufacturer). Required for subsea ROV, marine research, diving. Cost differential: IP65 baseline. IP67 +5-10%. IP68 +25-40%.
What O-ring material should I choose?
Silicone: temperature range -60°C to +200°C, excellent UV and ozone resistance. Standard for MIL-PRF-GRF tactical cases. Nitrile (NBR): temperature range -40°C to +120°C, good oil and chemical resistance. Standard for commercial IP67 cases. EPDM: temperature range -50°C to +150°C, excellent weather and chemical resistance. Used for outdoor / marine. Viton (FKM): temperature range -20°C to +200°C, excellent chemical and high-temperature resistance. Premium for harsh chemical environments. O-ring compression: 20-30% for proper seal.
When do I need a pressure-equalisation valve?
Always for altitude-change operations: helicopter cargo (rapid pressure changes), mountain operations (altitude changes during transport), aircraft cargo holds (rapid pressurisation changes during flight), ROV launch / recovery (surface-to-subsea transitions). Without pressure valve: case may pop open on descent (high to low altitude) or become impossible to open on ascent (low to high altitude). Automatic valve (Gore-Tex membrane) standard on IP67 cases. Manual valve for subsea ROV launch.
What material is best for waterproof cases?
PP copolymer: standard for IP65/IP67 cases. Good impact resistance, low cost. Wall thickness 3-5mm. Glass-filled PP (10-30% glass): premium stiffness for IP68 cases. Required for MIL-PRF-GRF load test. Wall thickness 4-6mm. PA (Nylon) blends: extreme temperature range (-40°C to +80°C). Used for subsea and aerospace applications. Cost USD 4-6/kg.
What is the MOQ for waterproof cases?
Tier 1 stock waterproof: 50-100 cases, USD 95-180/unit, 7-15 days production. IP65/IP67 standard. Tier 2 custom OEM waterproof: 100-300 cases, USD 130-280/unit (case + foam + valve), 7-15 days production. Tier 3 new mould waterproof: 1,000+ cases amortised, USD 90-220/unit post-amortisation, 60-90 days mould + 30-45 days production. IP68 deep rated.
How do I verify a waterproof case IP rating?
Four verification steps: (1) Request batch test certificate per lot (not factory-wide). (2) Verify test parameters: IP67 = immersion 1m / 30 min. IP68 = immersion depth + duration specified. (3) Verify the O-ring material matches deployment (silicone / nitrile / EPDM / Viton). (4) Cross-check lot number on certificate matches lot physically shipped. Procurement trap: factory has 2020 IP67 certificate. If mould design, O-ring material, or supplier changed, certificate no longer applies. Always request certificate dated within 12 months of shipment.