I need one of the hat bill mounted led lights for night time bass fishing to help when i need to retie a lure or do whatever while out in my boat...
the "do whatever" is pretty open ended. as such, an answer is difficult. for nearly anything that you'll do in the boat, including tying the lures a real bright thrower is NOT necessary and is probably detrimental. ignoring the "do whatever" for a moment and restricting ourselves to the clearly stated objectives, a small multiple 5mm LED light is all that is necessary. two levels of light o.p. might(???) be nice too. when it comes to lights like this, here is my suggestion:
Pak-Lite, the 9volt light. all are powered by a 9V "transistor", as they used to be called, battery.
all have 2x5mm LEDs.
it comes in different color of LEDs (for preserving one's dark adaptation) as well as WHITE.
all but the most basic model have two levels of light o.p., viz. LO and HI. LO is dim and is perfect for having minimal impact on one's dark adaptation. HI is bright enough for use as a task/proximity light - anything out to 10+ feet and further indoors or anywhere there is a lot of nearby reflective surfaces (like in a boat).
several models come with two different color LEDs (one white, the other a different color - with only one light level from either.).
burntimes are VERY LONG (especially on LO).
all are relatively inexpensive.
accessories include a wrist lanyard, mounting brackets for hard surfaces, and various means of attaching it to one's ballcap visor/brim, e.g. STICKY-back (real sticky - won't come loose in my experience) magnetic strips, and STICKY-back (ibid) velcro strips.
these have replaced my small Li coin cell powered lights in my arsenal. the Pak-Lite is so much better. just Google "Pak-Lite".
for distance viewing, go with the others' suggestions of a nice Fenix (or similar) light - they do clip very nicely to one's ballcap brim/visor - i've use them for night hiking.
my two shekels.