The great thing about 3D printing is you can over engineer a thing at little cost-
this is a clamp to hold an ESP8266 12F in its jig - the jig uses simple sprung wires to hold the chip in place - slightest touch or vibration and it pops out. So clamp it down securely with an over engineered clamp. Works for me.
I reworked the G clamp by joehann - shortened the neck, added a new base and altered the screw height and shape a bit

ELEGOO

ELEGOO NEPTUNE

No

Yes

0.2

30%

Neptune 4

The clamp allows jumper wires to be attached to the board on both sides