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Fixed Spool Reel

Arguably the hardest worked piece of equipment you will ever buy so get the best you can possibly afford.

Look for

Wide shallow spools for good casting.
Smooth quiet action for good control.
Good size for you - one that you can control the release of line with the bale arm open.
Rear Drag - stops line breaking especially when unexpectedly hooking a bigger fish.
Bail Arm action - one that opens smoothly and closes instantly every time without undue clatter.
Line rollers that work well.
Good balance - one that rotates smoothly without any wobble.
Standard size - avoid small reels
Modern manufacturing methods have made great strides and there are plenty of first class reels available at modest prices. Get the best you can afford - Get a well known brand
If its a make you don't recognise check the availability of spare parts.

Do keep it cleaned and lubricated - Get a reel case to protect your investment.