2025 Ronstan Marine Catalogue - Catalog - Page 38
SPORTS BLOCKS
Series 55 Orbit
36
RF56530
RF56510
Auto and manual ratchet
modes
(select models)
Integrated low
profile becket
RF55410
see page 30
RF56330B
RF56151
RF48209
see page 17
RF56151A
DSH-6GRY
see page 232
RF56330B
2 x 5mm (3/16”)
9:1 MAINSHEET
SYSTEM
RF150
4.8mm (3/16”) pin
RF56330B - Underhung becket is suitable for
terminating the sheet, or attachment of a
‘piggyback’ block for greater purchase*2.
Ultra-low profile integrated hollow hub becket
on fiddle blocks.
PRODUCT No.
Swivel shackle head fitting: Grade 316
stainless steel.
Swivel shackle head for unlimited block rotation.
RF56330B when paired with a RF55410 and a RF45209
lashed to the becket with a DSH-6GRY or RF900409, produces a powerful 9:1 mainsheet system for
use on catamarans to 5.5m (18ft). 8mm (5/16) rope
recommended.
DESCRIPTION
Ball Bearing
RF56151
Cheek block, clockwise, auto and manual, swivel shackle head
RF56151A
Cheek block, anti-clockwise, auto and manual, swivel shackle head
Triple block, underhung becket, adjustable cleat, auto,
RF56330B
swivel shackle head
RF56510
Fiddle block*1, becket, auto and manual, swivel shackle head
RF56530
Fiddle block*1, becket, adjustable cleat, auto, swivel shackle head
SHEAVE
DIAM.
mm
MAX. PIN
ROPE DIAM. M.W.L.
mm mm
kg
B.L. WEIGHT
kg
g
SHEAVE
DIAM.
in.
MAX. PIN
ROPE DIAM. M.W.L.
in.
in.
lb
55
55
10
10
-
250
250
700
700
76
76
2 5/32
2 5/32
3/8
3/8
-
55
10
5
750*2&3 1500
392
2 5/32
3/8
3/16
55 + 35
55 + 35
10
10
5
5
250
250*3
112
235
2 5/32 + 1 3/8
2 5/32 + 1 3/8
3/8
3/8
3/16
3/16
750
750
*1 Fiddle sheave has a high load full contact bearing (i.e. not ball bearing). Main sheave has 2-stage, ball bearing.
*2 Total block load. Load on underhung becket not to exceed 33% of block load. i.e. MWL 250kg (700lb), BL 500kg (1100lb). Underhung becket suits attachment of ‘piggyback’ block for creation of 7:1 or greater purchase.
*3 Line load through cleat not to exceed 175kg (385lb).
550
550
B.L. WEIGHT
lb
oz
1540
1540
2.7
2.7
1650*2&3 3300
13.8
550
550*3
1650
1650
3.9
8.3
