Please be aware:

• Unlike the general perception, even as little as 8-10 mm of free space between propeller and hull will be fine on most boats.
• Due to the nature of the propeller construction, folding blades are positioned further aft than a fixed propeller (see hub length) and thereby leave more space between shaft and hull.

Hub length, ISO standard shaft

Hub length (A), 2-blade
22 mm shaft, 1:10 taper = 88 mm ≈ 3.5″
25 mm shaft, 1:10 taper = 110 mm ≈ 4 3/8″
30 mm shaft, 1:10 taper = 130 mm ≈ 5 1/8″

Hub length (A), 3-blade up to 22″
25 mm shaft, 1:10 taper = 120 mm ≈ 4 47/64″
30 mm shaft, 1:10 taper = 136 mm ≈ 5 23/64″
35 mm shaft, 1:10 taper = 146 mm ≈ 5 3/4″
40 mm shaft, 1:10 taper = 156 mm ≈ 6 9/64″
45 mm shaft, 1:10 taper = 196 mm ≈ 7 23/32″

Hub length (A), 3-blade >22″ and 4-blade
35 mm shaft, 1:10 taper = 148 mm ≈ 5 53/64″
40 mm shaft, 1:10 taper = 157 mm ≈ 6 3/16″
45 mm shaft, 1:10 taper = 196 mm ≈ 7 23/32″
50 mm shaft, 1:10 taper = 206 mm ≈ 8 1/8″

Blade length

Blade length (B), 2-blade propeller:
12″ = 139 mm ≈ 5 31/64″
13″ = 152 mm ≈ 6″
14″ = 165 mm ≈ 6.5″
15″ = 177 mm ≈ 7″
16″ = 190 mm ≈ 7.5″
17″ = 203 mm ≈ 8″
18″ = 215 mm ≈ 8 15/32″

Blade length (B), 3-blade propeller:
14″ = 151 mm ≈ 6″
15″ = 163 mm ≈ 6 27/64″
16″ = 176 mm ≈ 6 15/16″
17″ = 189 mm ≈ 7 29/64″
18″ = 202 mm ≈ 7 61/64″
19″ = 216 mm ≈ 8 1/2″
20″ = 227 mm ≈ 8 15/16″
22″ = 282 mm ≈ 11 7/64″

Blade length (B), 4-blade propeller:
25″ = 275 mm ≈ 10 53/64″

Hub length, SAE standard shaft

Hub length (A), 2-blade
3/4″ shaft, 1:16 taper = 100 mm ≈ 4.0″
7/8″ shaft, 1:16 taper = 115 mm ≈ 4.5″
1″ shaft, 1:16 taper = 130 mm ≈ 5 1/8″
1 1/8″ shaft, 1:16 taper = 142 mm ≈ 5 19/32″
1 1/4″ shaft, 1:16 taper = 157 mm ≈ 6 3/16″

Hub length (A), 3-blade up to 22″
1″ shaft, 1:16 taper = 136 mm ≈ 5 23/64″
1 1/8″ shaft, 1:16 taper = 146 mm ≈ 5 3/4″
1 1/4″ shaft, 1:16 taper = 156 mm ≈ 6 9/64″
1 1/2″ shaft, 1:16 taper = 194 mm ≈ 7 41/64″
1 3/8″ shaft, 1:16 taper = 177 mm ≈ 7″
1 3/4″ shaft, 1:16 taper = 210 mm ≈ 8 9/32″

Hub length (A), 3-blade >22″ and 4-blade
1 1/2″ shaft, 1:16 taper = 202 mm ≈ 8″
1 3/4″ shaft, 1:16 taper = 210 mm ≈ 8 9/32″
2″ shaft, 1:16 taper = 275 mm ≈ 10 53/64″

Propeller diameter

12″ = 305 mm
13″ = 330 mm
14″ = 356 mm
15″ = 381 mm
16″ = 406 mm
17″ = 432 mm
18″ = 457 mm
20″ = 508 mm
19″ = 485 mm
21″ = 533 mm
22″ = 559 mm
24″ = 610 mm (3-blade propeller)
24″ = 625 mm (4-blade propeller)
25″ = 635 mm

Hub length, IMP standard shaft

Hub length (A), 2-blade

3/4″ shaft, 1:12 taper = 96,5 mm
1″ shaft, 1:12 taper = 110 mm ≈ 4 3/8″
1 1/4″ shaft, 1:12 taper = 129 mm ≈ 5 5/64″

Hub length (A), 3-blade up to 22″
1″ shaft, 1:12 taper = 116 mm ≈ 4 37/64″
1 1/4″ shaft, 1:12 taper = 136 mm ≈ 5 23/64″
1 1/8″ shaft, 1:12 taper = 120 mm ≈ 4 47/64″

Hub length (A), 3-blade >22″ and 4-blade
1 3/4″ shaft, 1:12 taper = 196 mm ≈ 7 23/32″

Hub length (A), saildrive
Hub for 2-blade propeller = 135 mm
Hub for 3-blade propelelr = 135 mm

2-Blade propeller for saildrive

2-Blade propeller for shaft

3-Blade propeller for saildrive

3-Blade propeller for shaft