You can buy them or make your own (closet rod pole cut to fit with rubber cabs on ends).
Should use 2.......one each side towards top/side of slide out.
BUT real question is......why is slide out extending (even a little bit) while in transit :H
Motor driven....worn clutch/motor brake?
Hydraulic.......leaking solenoid/valves, leak in ram seals?
Unless mfg. supplied locking bars (due to design/CYA)...they really shouldn't be needed IF system is working correctly
Is it time for your medication or mine?
2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
US NAVY------USS Decatur DDG31