Pan head machine screw | Phillips drive PH | A4 | DIN 7985
Pan head machine screw with Phillips (PH) recess in acid-proof stainless steel A4 (AISI 316), also known as an MRX screw, cross-head screw, lens head screw, or pan head cross-recess screw, is intended for use in outdoor, industrial, and marine environments. The product complies with DIN 7985 (replaced by ISO 7045) and is used where a low-profile, metric screw connection with a pan head and cross recess is required. It is suitable for professional installations where long service life and consistent performance are essential.
FIELD OF APPLICATION
The pan head machine screw is used in electronics and appliance manufacturing, instruments, cabinets and enclosures, fittings, boat and marine installations, the food industry, and general mechanical assembly. It is intended for applications where the screw is driven into a nut or threaded hole using a standard Phillips screwdriver or bit, and where the material selection provides the necessary protection against corrosion and mechanical stress. The acid-proof machine screw is available in dimensions M1.6, M2, M2.5, M3, M4, M5, M6, and M8 in lengths from 3 to 100 mm.
TECHNICAL SPECIFICATIONS
- Product type: Screw
- Product family: Pan head machine screw (MRX, cross-head screw, lens head screw, metric pan head screw)
- Material class: A4 (AISI 316, acid-proof)
- Standard: DIN 7985 (substantially equivalent to ISO 7045)
- Thread dimension: M1.6–M8, metric thread
- Drive type: Phillips cross recess, type H (PH)
- Design: Pan head (lens head), threaded
- Environment: Marine / Outdoor
- Delivery unit: Piece
FREQUENTLY ASKED QUESTIONS (FAQ)
What is a pan head machine screw according to DIN 7985?
DIN 7985 describes machine screws with a metric thread, pan head (lens head), and cross recess. In Sweden, the screw is often called MRX or cross-head screw. The standard has been replaced by ISO 7045, which has essentially the same design but slightly different head dimensions in certain sizes.
What is the difference between Phillips (PH) and Pozidriv (PZ)?
This screw has a Phillips cross recess, type H, and must be driven with a PH bit or PH screwdriver. Pozidriv (type Z, PZ) has additional markings between the arms of the cross and a different recess geometry. Always use bits that match the recess type, otherwise, the risk of the bit slipping out and damaging the recess increases. For stainless steel screws, stainless steel Phillips bits are recommended to avoid cross-contamination rust.
Which bit size should I use?
As a guideline, PH1 is used for M2.5–M3, PH2 for M4–M5, PH3 for M6, and PH4 for M8. For the smallest dimensions, M1.6–M2, PH0 or PH1 is used depending on the design.
How is the length of a pan head machine screw measured?
The length is measured from the underside of the head to the tip of the screw; the head is therefore not included. Choose the length based on the thickness of the parts to be fastened as well as the height of any washer and nut.
What is the difference between A2 and A4?
A4 (AISI 316) contains molybdenum and withstands chlorides better than A2 (AISI 304). Choose A4 for marine environments, coastal locations, or chemical exposure, and A2 for general indoor and outdoor use. In cases of constant seawater contact or oxygen-deprived crevices, even A4 can be susceptible to crevice corrosion.
What is the difference compared to a pan head hex socket screw according to DIN 7380?
DIN 7380 has a hex socket and a lower, wider head, whereas DIN 7985 has a cross recess and is driven with a standard Phillips screwdriver or bit. See also Pan head hex socket screw A4 DIN 7380.