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Adjustable trip point anywhere between 1 inches Hg to 6 inches Hg.
The trip level adjustment is by common 5/64 or 2mm hex (Allen) wrench, included.
The switch has normally open, normally closed contacts.
1/4 and 5/16 inch (6.4mm and 8mm) combo port.
4 - 3/16 (4.8mm) quick connectors included.  2 red for 18-22 gauge wire and 2 blue for 14-16 gauge wire.
Also included is a 1/4" vacuum tee.
Switch has hole for mounting screw.
Same switch, from the same manufacturer, included in popular  torque convertor lockup kits.
Could be used for 700-R4 or 200-4R converter lock-up or any other use you can think of.

Electrical ratings: Microswitch Model #V7-3E17D8-000-3
                           10A 1/3HP 125, 250,277 VAC
                           1/2A 125 VDC  1/4A 250 VDC
                           4A 125 VAC L

Shipping price for US, others, email for cost first.