Got fed up with the boot dropping down on my back so sent the struts to SGS for re-gassing. Excellent customer service, sent an email with some questions and they replied next day. All told £36 to re-gas, I thought were excellent value, and returned within a day of receiving. Tip take a photo and perhaps label; which side, and way up the struts go. I didn't and therefore had to figure it out, wasn't too difficult but put them on the wrong way around first. Amazed how heavy a boot is without the gas struts. Some before and after photos attached not that they show much.