Let me start by saying these Duracell N batteries saved my vintage HP calculator collection! After hunting for this obscure size locally, Amazon delivered them overnight (seriously, faster than my pizza).

The good stuff first: These copper-tops pack serious longevity. My dinosaur baby toy is still roaring after 3 months of toddler abuse. Unlike cheap brands I've tried, zero leaks - crucial for my delicate calculator contacts.

Now the reality check: At over $2 per battery, I winced harder than when I stub my toe. Also noticed the diameter's slightly larger than my old batteries - they fit but protrude like a muffin top in tight jeans. Not ideal for sleek devices.

Pro tip: Double-check your device's battery compartment depth before buying. While they worked in my antique lighter's bulb circuit, the snug fit had me nervous during installation.

Final verdict? When you absolutely need reliable power for niche devices (medical gear, fancy key fobs), these deliver despite the premium price. Just maybe don't use them in your heirloom grandfather clock unless you're okay with a slight bulge.