25mm XL Flat Top Clear Round Bottom Banger

Round bottoms are going to allow your flame to naturally curve around, using more of the residual flame to heat the banger.

Round bottoms typically have a 3mm wall thickness, whereas most flat bottoms have a 2-2.5mm wall thickness but they have a 4mm base.

Round bottoms allow your oil to move around inside of your banger easier since the concentrate is moving to the center as you splash it back up, whereas a flat bottom you need to physically move the oil around a bit more - use a terp pearl for a better dab experience.