Switchcraft 12B
1/4" Stereo 3-Conductor Jack with Nut & Washer, Double-Open Circuit

OUR PART #  12B


The Switchcraft 12B is a double open circuit 1/4" stereo 3-conductor jack with nut and washer. MIL jacks mate with MIL-type phone plugs with 0.25" (6.35mm) or 0.21" (5.34mm) diameter bushings.

Switchcraft 12B Specifications:

Mechanical Specifications:

  • Life, Commercial Jacks: 10,000 insertion/withdrawal cycles, minimum.
  • Life, Military Jacks: 20,000 insertions/withdrawals, minimum.
  • Mechanical Shock: Military Jacks - Per MIL-STD 202, method 213, Test Condition H (75g).
  • Vibration: Military Jacks - Per MIL-STD-202, method 213, (10-55 Hz).

Electrical Specifications:

  • Contact Resistance
         * Commercial Jacks -.030 ohms max (initial), .050 ohms max (after humidity, durability exposure). Per MIL-STD-202E.
         * MilitaryJacks - .010 ohms max (initial), .020 ohms max (after life), .10 ohms max (after salt spray).
  • Insulation Resistance:
         * Commercial Jacks-10,000 M(omega) min (initial), 1,000 M(omega) min (after humidity).
         * Military Jacks - 10,000 M(omega)min (initial), 1,000 M(omega) min (after humidity, durability exposure).
  • Dielectric Withstanding Voltage: 500 V, 60 Hz (rms) AC.
  • Contact Rating: 1 A, 25 V DC.

Environmental Specifications:

  • Thermal Range:
         * Commercial Jacks; -55°Cto+85°C (non- operating); -20°C to +65°C (operating)
         * Military Jacks; -55°C to+85°C (non-operating); -40°C to +65°C (operating)
  • Thermal Shock:
         * Commercial Jacks - Per MIL-STD202, method 107
         * MilitaryJacks - Per MIL-STD 202, method 107
  • Humidity:
         * Commercial Jacks - Per MIL-STD202, method 106
         * MilitaryJacks - 0% to 95% operating and non-operating
  • Salt Spray:
         * Commercial Jacks - Per MIL-STD202, method 101
         * MilitaryJacks - Per MIL-STD 202, method 101 (48 hours)
  • Moisture Resistance: Military Jacks - Per MIL-STD 202, method 106 (240hours)

Material Specifications:

  • Mounting Bushing: Nickel-plated copper alloy.
  • Insulation: Rigid plastic.
  • Springs: Special copper alloy. Integral contacts are standard in the isolated switching circuits; fine silver contacts in C12A switching circuit.
  • Sleeve Terminal: Copper alloy.
  • Hardware: Supplied with one Number P10001 copper alloy nickel-plated hex nut, and one Number S1022 steel nickel-plated washer - except copper alloy nickel-plated washer
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