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Westfield Fasteners Product Specification:

NF E 27-128 - Slotted Mushroom Head Screws

This product guide contains the specification for metric slotted mushroom head screws available from Westfield Fasteners. The basis of this specification is the French national standard NF E27-128.

Product Description

A wide headed, lower profile screw with a traditional slot drive. Used for bolting softer materials. This unusual fastener also known as a truss headed screw, and is always manufactured with a full thread.

Figure 1 and table 1 below define the overall dimensions and tolerances for slotted mushroom head screws.

Figure 1: Slotted Mushroom Head Screw

Table 1: Dimensions & Tolerances (mm)

d	thread pitch	dk	k	n	t	s
M3	0.50	6.9	2.0	0.8	0.95	0.8X4.0
M4	0.70	10.0	2.2	1.2	1.00	1.2X7.0
M5	0.80	12.5	2.7	1.2	1.20	1.2X7.0
M6	1.00	15.0	3.3	1.6	1.50	1.6X9.0
M8	1.25	20.0	4.4	2.0	2.00	2.0X12.0