Maxcatch Full Sinking Fly Fishing Line Fast Sinking, Slow Sinking Rate. Maxcatch SINKING lines: these will get your fly down to where the fish are, especially in fast, cold or bright conditions. Starting in his garage with nought but a few tools, a dream, and a single product – a fly box handcrafted by himself – Maxcatch began to flourish, quickly escalating in size, scope and ambition.