Installation: 2“ x 3”: This caliber is the right size and does not require crimping. Direct Connection To Downpipe: 3“ x 4”: If using a downpipe without a crimped end, some pressure is needed to connect, but the seal will be better. If you use the crimped end, it can be connected directly with less effort. You can DIY it according to your needs! Features: We have lengthened the butt joints for a more secure downpipe installation and thickened the overall design for optimal protection. Professional design: The offset design allows the downspout to fit snugly against the wall with the backside sloping back instead of entirely centered. This has the benefit of a flat back that fits perfectly against the wall. Color Options: White Provide Service: If you have any questions about the product, please feel free to consult the product customer service!