ESP-RA™ PLUG DESCRIPTION
The ESP-RA™ is the first solderable 1/4" phone connector from Evidence Audio and designed (like all of our products) with the primary purpose to sound demonstrably better than anything in its class.
What class does it fall in?  Its compact size and angled format makes it especially suitable for use with smaller cables on pedalboards specifically. Cables with an outer diameter of 4 mm, or around 0.155".
The current flood of plugs used to solder patch cables for a guitar pedalboard typically use a steel nail or pot metal to conduct the audio signal. Ferrous. Magnetic. While these plugs are compact for pedalboards, they cut corners by using inferior metals to carry the sound. They offer greater affordability yet greatly reduced audio quality.
MATERIALS
The contact points of the ESP-RA™ are machined from a high-copper-content brass. Brass offers the appropriate hardness and strength required for a connector with very good conductivity to minimize distortions caused by the cable the plugs are used on.
PATENT-PENDING DESIGN
The form factor is akin to a "pancake" style plug, with a patent-pending closure system that allows for the plug to be assembled with one screw instead of two. This allows for a smaller form-factor as well as reduced assembly time. 
HOUSING SIZE
Width 16 mm | Height 25 mm | Depth 8 mm
CABLE COMPATIBILITY
To give an idea of the cables appropriately sized to work with the ESP-RA plug here's a list of some better known makes and models, which are all compatible:
Evidence Audio Blackrock, Evidence Audio Monorail, Belden 1865A, Belden 8218, Bill Lawrence BL-150, BPTA CA 0492, BPTA CA 0678 Canare GS-4,  Free the Tone CU-418, George L's155, Mogami 2314, Sommer SC-ONYX TYNEE
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