The 16 mm is Harken’s smallest block. It is perfect for small synthetic control lines found on high-tech dinghies. The patented bearing system uses stainless steel balls in a captive grooved race and has a 250 lb (113 kg) maximum working load. The 442 uses a spacer to keep the line in the sheave during intermittent loading.
| Sheave Ø (mm) | 16 mm |
| Sheave Ø (in) | 5/8 in |
| Length (mm) | 35 mm |
| Length (in) | 1 3/8 in |
| Weight (g) | 12 g |
| Weight (oz) | .44 oz |
| Maximum line Ø (mm) | 5 mm |
| Maximum line Ø (in) | 7/32 in |
| Fasteners (mm) | 4 RH mm |
| Fasteners (in) | #8 RH in |
| Maximum working load (kg) | 113 kg |
| Maximum working load (lb) | 250 lb |
| Breaking load (lb) | 1200 lb |
| Breaking load (kg) | 544 kg |
| Mounting hole spacing (mm) | 27 mm |
| Mounting hole spacing (in) | 1 1/16 in |