Mask-Off Protex 5 Latex Saturated Protective Paper | 5 Mil | Aluminum Skin & Fabrication Protection | Boeing BAC 5034

The aerospace fabrication industry's go-to scratch prevention paper — printed in bold red ink with "SCRATCHES CAUSE REJECTIONS — HANDLE WITH CARE" to keep work crews accountable on the shop floor. Trusted by Boeing-approved facilities, Lockheed Martin, Gulfstream, and Bombardier MRO operations since 1950 for protecting exterior aluminum skins, electronic cabinetry, and bare metal surfaces during the most demanding fabrication processes. Protex 5 by Mask-Off is a 4–5 mil latex saturated paper engineered for scratch and abrasion protection of bare aluminum, titanium, stainless steel, and painted surfaces. Its natural latex adhesive holds reliably during active fabrication — the surface can be routed, drilled, countersunk, and riveted right through the paper without removal. A flat release liner allows the product to be die-cut into custom shapes and sizes for precise coverage. 

 Key Features

• "Scratches Cause Rejections" warning printed in red ink — Bold shop floor reminder keeps crews accountable and surfaces damage-free during fabrication
• Fabrication-ready protection — Surface can be routed, drilled, countersunk, and riveted through the paper without removal
• Natural latex adhesive — Reliable hold on aluminum, titanium, stainless steel, and painted surfaces without leaving residue
• Silicone-free adhesive — No silicone contamination risk on critical aerospace surfaces
• Die-cuttable — Flat release liner allows conversion into custom shapes and sizes
• Lightweight 4–5 mil construction — Thin and conformable for exterior aluminum skin and electronic cabinetry applications
• Boeing BAC 5034 approved — Meets Type IV, Class I, Grade A specification

Applications

• Exterior aluminum skin protection during aircraft fabrication and assembly
• Electronic cabinetry scratch prevention during manufacturing
• Bare aluminum, titanium, and stainless steel surface protection
• Painted surface protection during fabrication and transport
• Surfaces requiring routing, drilling, countersinking, and riveting through the tape
• Die-cut custom protection pieces for precision aerospace components

Specifications

• Backing — Latex saturated paper, printed red ink warning
• Adhesive — Natural latex (silicone free, PSTC-1 Modified)
• Liner — Flat (die-cuttable)
• Thickness — 4.1–5.1 mil (nominal 5 mil)
• Basis weight — 42–49 lbs / 3,000 sq. ft.
• Tensile strength — 12.7 lb/in (M.D. min.)
• Elongation — 6.0% M.D. min.
• Elmendorf Tear — 56 grams MD min. / 56 grams CD min.
• Adhesion to steel — 17–22 oz/in (at time of manufacture)
• Shelf life — 1 year when stored in a cool, dry place out of direct sunlight

Certifications & Approvals

• Boeing — BAC 5034, Type IV, Class I, Grade A
• NSN — 8135-00-946-2090

Important Notes

• Not intended for fly-away applications
• Test prior to use on copper, brass, or anodized aluminum
• Test prior to outdoor exposure