I used the garden hose threads from http://www.thingiverse.com/thing:26730 and adapted them to a large "watering can" style using http://www.thingiverse.com/thing:9535. I scaled up the spout part quite a bit and added additional holes. I used Tinkercad to model the in-between bit, which features a large chamber allowing the water to drip at low speed, even with very high water pressure. This allows us to water flowers with large amounts of water quickly without blasting them into oblivion. The walls are about 2mm thick, for a strong and durable printed part. I printed this one from ABS at 0.3mm layer height.