
Mantus swivel sizing and construction
The integrated shackle connects directly to the anchor, avoiding the side loading that can occur when a conventional shackle bears across a swivel eye. The body is precision-cast 316L stainless steel and the oblong chain pin is 2507 duplex stainless steel.
| Model | Nominal chain size; grade also determines fit | Working load limit | Ultimate breaking strength | Included anchor shackle |
|---|---|---|---|---|
| S1 | 1/4–5/16 in (6–8 mm) | 3,000 lb (1,360 kg) | 15,000 lb (6,804 kg) | 7/16 in (11 mm) |
| S2 | 5/16–3/8 in (8–10 mm) | 4,340 lb (1,970 kg) | 21,700 lb (9,843 kg) | 1/2 in (13 mm) |
| S3 | 3/8–1/2 in (10–13 mm) | 7,000 lb (3,175 kg) | 35,000 lb (15,876 kg) | 5/8 in (16 mm) |
Choose by chain grade as well as diameter
S1: 1/4 or 5/16 in Grade 30/40; 1/4 in Grade 70. S2: 3/8 or 7/16 in Grade 30; 3/8 in Grade 40; 5/16 in Grade 70. S3: 1/2 in Grade 30; 7/16 or 1/2 in Grade 40; 3/8 or 7/16 in Grade 70. Match the manufacturer chain-grade chart and verify anchor and bow-roller clearance.