What value fuse is this & what does it do? (Wife's Truck!)

[rwogs]

I've been chasing down a bad ground and/or a dirty contact in my wife's 1972 C10 Pickup. While probing around, I accidentally broke a glass fuse that was inside a rubber enclosure near the fusible link and battery. I have not yet dug either end out yet, but can someone tell me what type and amperage fuse it is and what it does? I need to repair it somehow. The vehicle seems to run without it. I've borrowed a couple of images from old posts that show where the fuse/thing is.
Thanks for any help you can give.

[VetteVet]

Easy answer . that is the fuse for the battery charge indicator,(ampmeter). It is 4 amps and there should be another one over on the left side of the radiator near the horn.

[rwogs]

Sweet! Thanks VetteVet. Next step is to fix that and then pull the steering wheel and check the turn signal switch. I read your post on checking that switch (very good) and it looks like I have an issue with the left turn portion of the switch.