Button-Head Lock-Tight Screws

Button-head screws with a pre-applied nylon locking patch that resists loosening under vibration.

Manufactured by Uvi Tech Fit in Kundli, Sonipat, India.

ISO 7380 head, patch per DIN 267-28

Button-Head Lock-Tight Screws (nylon patch screw) made by Uvi Tech Fit

Overview

Button-head washer-flange screws supplied with a pre-applied lock-tight nylon patch on the thread. The patch compresses between the mating threads, adding prevailing torque that resists loosening under vibration, without a separate washer or adhesive at assembly. Common on automotive, machinery, and appliance joints that see movement.

Also known as: nylon patch screw, pre-applied threadlock screw, self locking screw.

Used in

Automotive and ancillary assemblies
Machinery subject to vibration
Appliances and motors
Fitness and mobility equipment
Electronics and enclosure mounts
Serviceable locked joints

Dimensions

Button head, hex socket (ISO 7380-1)

Size	Head dia. dk	Head height k	Hex key s
M3	5.7	1.65	2
M4	7.6	2.2	2.5
M5	9.5	2.75	3
M6	10.5	3.3	4
M8	14.0	4.4	5

Flanged button heads follow ISO 7380-2. Give patch position and length along the thread.

Parts are checked at each stage with vernier calipers, micrometers and visual inspection. Material and test reports can be arranged on request.

Request a Quote

Give size, length, material, finish and quantity. For a custom part, attach a drawing or a photo of the sample.

Questions

How does a nylon patch lock?

The patch fills the gap between mating threads and adds friction (prevailing torque), so the screw resists turning loose under vibration.

Can the screw be reused?

Nylon patches can usually be reused a few times with reduced locking torque. Adhesive (micro-encapsulated) patches are single-use.

Where is the patch applied?

Usually a band a few threads from the tip, on one side or all round. Specify position and length if your assembly needs it.

Thread, hole and spanner size reference →