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Attwood Gas Springs: Extended = 36.3", Compressed = 21.1", PSI = 40 - 10 mm Rod
Price: $20.88
(Out of stock)
Save: $2.71
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Part # SL29-40-1
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Extended = 36.3", Compressed = 21.1", Stroke = 15.2", PSI = 40

Popular gas springs designed for marine, RV and automotive applications. Special Ni-Slide rod coating for excellent corrosion resistance. These gas springs can be used in salt water areas. Each gas spring has a 10 mm composite head socket fitting which is the standard size for ball stud style mounting brackets. The 6mm x 15mm (rod & cylinder dimensions) are lighter duty to standard applications. The 8mm x 18mm are for standard to heavy duty applications. Connectors sold seperately. E=Extended Length, C=Compressed Length, S=Stroke, P=Force(lbs.)

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Perfect match for replacing my springs
by James from oak Creek, Wisconsin on July 14, 2015
Works as expected.
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gas shocks
by Gregory from Southern Pines, North Carolina on June 24, 2012
i installed the same shocks per part number and ordered them with 10 pounds more lift than the originals and they would not hold up the they make a 60 pound lift with the same comp and extend measurements ?
(2 of 2 people found this review helpful)
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I would like to order SL29-40-1 but what is the correct mounting bracket..Same as the 30-1?
Everything is the same for the 30-1. The SL29 is the model, the rest of the numbers just indicate PSI and packaging. There is no part number for a mounting bracket in Attwood's catalog on these springs.

I intend to replace a SL 29-30 model with a SL29-40 model spring. The 30 model has a 13mm ball and the 40 model has a 10mm ball. Can I assume that I will have to replace the mounting brackets because of the different ball sizes?
SL29 refers to the size of 36" extended, 21" compressed, all SL29's use a 13mm socket. ST29 which is the stainless steel version uses a 10mm socket. As long as you stay with the SL29 series you won't have to change the ball mount you've been using.

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