RAM® Hole Pattern Reference Guide
2-Hole Patterns Imperial
Metric
Diameter
Diameter
B Size 1" Ball
1.91" (AMPS)
48.41mm
RAM-B-238U RAP-B-238U RAM-B-125BU
RAM-238U
-
1.5"
38.1mm
RAM-B-202U-12
RAM-202U-12
-
2.09 - 2.76"
53 - 70.1mm
RAM-B-346U
-
-
2.437"
61.9mm
RAM-B-247U-2NHB
RAM-247U-2NHB
-
2.52"
64mm
RAM-B-202U-CRO1
RAM-202U-CRO1
RAM-D-202U-CRO1
4.73"
120.14mm
-
RAM-270U
-
2.75"
69.85mm
-
RAM-240U
RAM-D-202U
C Size 1.5" Ball
D Size 2.25" Ball
D Size 2.25" Ball Holds 6 lbs
3-Hole Patterns
C Size
Imperial
Metric
1.5" Ball Holds 4 lbs
Diameter
Diameter
B Size 1" Ball
1.81"
46mm
RAM-B-202U
RAM-202U
RAM-D-254-WD1U
2.75"
69.85mm
-
RAM-240U
RAM-D-202U
C Size 1.5" Ball
D Size 2.25" Ball
B Size 1" Ball Holds 2 lbs
4-Hole Patterns Imperial 4-Hole
Metric Diagonal 2-Hole
4-Hole
Diagonal 2-Hole
B Size 1" Ball
C Size 1.5" Ball
D Size 2.25" Ball
.75" x 4.33"
4.39"
19.05mm x 109.98mm
111.5mm
RAM-B-111BU
RAM-111BU RAP-111BU
RAM-D-115BU
1" x 2"
2.24"
25.4mm x 50.8mm
56.9mm
RAM-B-202U-1525
RAM-202U-1525
-
1" x 2.5"
2.69"
25.4mm x 63.5mm
68.33mm
RAM-B-202U-153
RAM-202U-153
-
1" x 1.5"
1.8"
25.4mm x 38.1mm
45.72mm
RAM-B-202U-152
RAM-202U-152
-
1" x 1.748"
2.01"
25.4mm x 44.4mm
51.15mm
RAM-B-202U-CRO1
RAM-202U-CRO1
RAM-D-202U-CRO1
RAM-202U RAM-347U RAP-202U RAP-111BU
RAM-D-254U RAM-D-254-WD1U
1.181" x 1.496" (AMPS)
1.91"
30mm x 38mm
48.41mm
RAM-B-202U RAM-B-347U RAP-B-202U RAP-B-347U RAM-B-125BU
1.25" x 2.85"
3.11"
31.75mm x 72.39mm
79mm
RAM-B-111BU
RAM-111BU RAP-111BU
RAM-D-115BU
1.25" x 3.56"
3.77"
31.75mm x 90.42mm
95.76mm
RAM-B-111BU
RAM-111BU RAP-111BU
RAM-D-115BU
1.25" x 5"
5.15"
31.75mm x 127mm
130.81mm
-
-
RAM-D-111BU
1.25" x 5.5"
5.64"
31.75mm x 139.7mm
143.26mm
RAM-B-111BU
RAM-111BU RAP-111BU
RAM-D-115BU
1.28" x 1.39 - 2.23"
1.89" - 2.57"
32.51mm x 35.3 56.6mm
48 - 65.28mm
RAM-B-346U
-
-
1.38" x 2.95"
3.26"
35mm x 75mm
82.76mm
-
RAM-2462U
RAM-D-2462U
1.5" x 1.5"
2.12"
38.1mm x 38.1mm
53.85mm
RAM-B-202U-22
RAM-202U-22
RAM-D-202U-22
1.5" x 2"
2.5"
38.1mm x 50.8mm
63.5mm
RAM-B-202U-225 RAP-B-202U-225
RAM-202U-225 RAP-202U-225
RAM-D-202U-225
1.5" x 2.5"
2.92"
38.1mm x 63.5mm
74.17mm
RAM-B-202U-23
RAM-202U-23
RAM-D-202U-23
1.5" x 3.5"
3.81"
38.1mm x 88.9mm
96.77mm
RAM-B-202U-24
RAM-202U-24
RAM-D-202U-24 RAM-D-111BU
1.5" x 4.5"
4.74"
38.1mm x 114.3mm
120.4mm
RAM-B-202U-25 RAM-B-111BU
RAM-202U-25 RAM-111BU RAP-111BU
RAM-D-202U-25 RAM-D-115BU
1.5" x 6.75"
6.91"
38.1mm x 171.45mm
175.51mm
-
-
RAM-D-111BU
1.5" x 9"
9.12"
38.1mm x 228.6mm
231.65mm
-
-
RAM-D-111BU
1.5" x 10.5"
10.61"
38.1mm x 266.7mm
269.5mm
-
-
RAM-D-111BU
1.875" x 1.875"
2.65"
47.63mm x 47.63mm
67.31mm
RAM-B-107BU
RAM-107BU
-
1.97" x 3.94"
4.4"
50mm x 100mm
111.8mm
-
RAM-243U RAM-246U
RAM-D-243U RAM-D-246U
2" x 2"
2.83"
50.8m x 50.8mm
71.88mm
RAM-B-202U-2525
RAM-202U-2525
-
2.95" x 2.95"
4.18"
75mm x 75mm
106.07mm
-
RAM-2461U RAM-246U
RAM-D-2461U RAM-D-246U
3" x 4.062"
5.05"
76.2mm x 103.17mm
128.27mm
-
RAM-246U
RAM-D-246U
3.94" x 3.94"
5.57"
100mm x 100mm
141.42mm
-
RAM-246U
RAM-D-246U