Metric Tolerances (mm):

Nominal Dimension		A1		A2		A3		A4
above	up to andincluding	Fixed	Closure	Fixed	Closure	Fixed	Closure	Fixed	Closure
0	10	0.1	0.13	0.16	0.2	0.2	0.32	0.32	0.8
10	16	0.13	0.16	0.2	0.25	0.25	0.4	0.4	0.9
16	25	0.16	0.2	0.2	0.32	0.32	0.5	0.5	1
25	40	0.2	0.25	0.32	0.4	0.4	0.63	0.63	1.12
40	63	0.25	0.32	0.4	0.5	0.5	0.8	0.8	1.25
63	100	0.32	0.4	0.5	0.63	0.63	1	1.1	1.4
100	160	0.4	0.5	0.63	0.8	0.8	1.25	1.25	1.6
160 & over (Multiply by)				x .004	x .005	x .005	x .008	x .008	x .010

Inch Tolerances (in):

Nominal Dimension		A1		A2		A3		A4
above	up to and including	Fixed	Closure	Fixed	Closure	Fixed	Closure	Fixed	Closure
0	0.40	0.004	0.005	0.006	0.008	0.008	0.013	0.013	0.032
0.40	0.63	0.005	0.006	0.008	0.010	0.010	0.016	0.016	0.036
0.63	1.00	0.006	0.006	0.010	0.013	0.013	0.020	0.020	0.040
1.00	1.60	0.008	0.010	0.013	0.016	0.016	0.025	0.025	0.045
1.60	2.50	0.010	0.013	0.016	0.020	0.020	0.032	0.032	0.050
2.50	4.00	0.013	0.016	0.020	0.025	0.025	0.040	0.040	0.056
4.00	6.30	0.016	0.020	0.025	0.032	0.032	0.050	0.050	0.063
6.30 & over (Multiply by)				x .004	x .005	x .005	x .008	x .008	x .010

Table 12. Summary of RMA Drawing Designations Extruded Rubber Products:

RMA Class	Dimensional Tolerance* Table 13	CutLength Tolerance* Table 16	SplicedLength Tolerance* Table 16	MandrelCured* Table 20
1	E1	L1	S1	EN1
2	E2	L2	S2	EN2
3	E3	L3	S3	EN3
–	–	–	–	–

Table 13. Standard Cross-Sectional Tolerance:

RMA Class		1 – High Precision	2 – Precision	3 – Commercial
Drawing Designation		E1	E2	E3
Dimensions (in Millimeters)
Above	Up to and including
0	1.5	+0.15	+0.25	+0.4
1.5	2.5	0.20	0.35	0.50
2.5	4	0.25	0.40	0.70
4	6.3	0.35	0.50	0.80
6.3	10	0.40	0.70	1.00
10	16	0.50	0.80	1.30
16	25	0.70	1.00	1.60
25	40	0.80	1.30	2.00
40	63	1.00	1.60	2.50
63	100	1.30	2.00	3.20
RMA Class		1 – High Precision	2 – Precision	3 – Commercial
Drawing Designation		E1	E2	E3
Dimensions (in Inches)
Above	Up to and including
0	0.06	+0.006	+0.010	+0.015
0.06	0.10	0.008	0.014	0.020
0.10	0.16	0.010	0.016	0.027
0.16	0.25	0.014	0.020	0.031
0.25	0.39	0.016	0.027	0.039
0.39	0.63	0.020	0.031	0.051
0.63	0.98	0.027	0.039	0.063
0.98	1.57	0.031	0.051	0.079
1.57	2.48	0.039	0.063	0.098
2.48	3.94	0.051	0.079	0.126

Table 16. Cut Length tolerance for unspliced extrusion:

1 – HighPrecision  2 -Precision  3 – Commercial
Drawing Designation.		L1	L2	L3
Length (in Millimeters)
Above	Up to and including
0	40	+0.7	+0.04	+1.6
40	63	0.08	1.3	2.0
63	100	1.0	1.6	2.5
100	160	1.3	2.0	3.2
160	250	1.6	2.5	4.0
250	400	2.0	3.2	5.0
400	630	2.5	4.0	6.3
630	1000	3.2	5.0	10.0
1000	1600	4.0	6.3	12.5
1600	2500	5.0	10.0	16.0
2500	4000	6.3	12.5	20.0
4000		0.16%	0.32%	0.50%
Length (in Inches)
Above	Up to and including
1	1.6	+0.03	+0.04	+0.06
1.6	2.5	0.03	0.05	0.08
2.5	4	0.04	0.06	0.10
4	6.3	0.05	0.08	0.13
6.3	10	0.06	0.10	0.16
10	16	0.8	0.13	0.20
16	25	0.10	0.16	0.25
25	40	0.13	0.20	0.40
40	63	0.16	0.25	0.50
63	100	0.20	0.40	0.63
100	160	0.25	0.50	0.80
160		0.16%	0.32%	0.50%

Table 18. Spliced Length Tolerances:

RMA Class		1 – High Precision	2 – Precision	3 – Commercial
Drawing Designation		S1	S2	S3
Millimeters
Above	Up to and including
0	250	+302	+3.2	+7.1
250	400	4.0	7.1	8.0
400	630	5.0	8.0	9.0
630	1000	6.3	9.0	10.0
1000	1600	8.0	10.0	11.2
1600	2500	10.0	11.2	12.3
2500	over	012.5	12.5	16.0
Inches
Above	Up to and including
0	10	+.13	+.25	+.28
10	16	.16	.28	.32
16	25	.20	.32	.36
25	40	.25	.36	.40
40	63	.32	.40	.45
63	100	.40	.45	.50
100	over	.50	.50	.53

Table 20. Tolerances on Internal Dimensions of Mandrel-Supported Extrusions:

RMA Class		1 – High Precision	2 – Commercial	3 – Non-Critical
Drawing Designation		EN1	EN2	EN3
Nominal Dimensions (in Millimeters)
Above	Up to and including
0	4	+0.20	+0.20	+0.35
4	6.3	0.20	0.25	0.40
6.3	10	0.25	0.35	0.50
10	16	0.35	0.40	0.70
16	25	0.40	0.50	0.80
25	40	0.50	0.70	1.00
40	63	0.70	0.80	1.30
63	100	0.80	1.00	1.60
100	160	1.00	1.30	2.00
160		0.6%	0.8%	1.2%
Nominal Dimensions (in Inches)
Above	Up to and including
0	0.16	+0.008	+0.08	+0.014
0.16	0.25	0.008	0.010	0.016
0.25	0.40	0.010	0.014	0.020
0.4	0.63	0.014	0.016	0.028
0.63	1.00	0.016	0.020	0.032
1.00	1.6	0.020	0.028	0.040
1.6	2.5	0.028	0.032	0.051
2.5	4.00	0.032	0.040	0.063
4.00	6.30	0.040	0.051	0.079
6.30		0.6%	0.8%	1.2%

Keep in mind that the RMA tolerance charts are typically specific to the type of rubber product you are using and the specific application. Be sure to carefully review chart to ensure that it is appropriate for your needs.

When in doubt, always ask! Feel free to contact us with any of your queries and we will be happy to assist you.