The Ryobi 18 volt/lithium rechargeable battery caulking gun should be among every DIY and pro's caulking gun tools. We used the rechargeable gun to apply interior construction adhesive to 4 buildings (500' x 50') to close-up gaps between cinder block and luan to prevent air flow entering when large industrial fans are drawing - causing static pressure build up. This caulking gun has a bead selection range from narrow to wide (depending on how much angle and where you cut the tube point). Initially, we were disappointed because this gun only takes the 11.5 - 12.2 tubes of adhesive. But what we found from others using guns that take large tubes is that the larger tubes cause the gun to weigh about 2lbs more. I am a female and used 15 tubes in 3.5 hrs had no problem handling weight of gun with 12 oz tube. I would suggest you have strong metal rod to poke the internal seal as this is not on the gun as is on manual caulking guns and if you attempt to apply pressure - you may push through the back of the adhesive tube. The gun maintained good power for approximately 4 hrs. I purchased two guns and two extra batteries to keep charged at all times. I cleaned the gun with soap, ammonia, and water to keep adhesive from drying and clogging (especially at base). Simple construction. Also, the same Ryobi lithium batteries can be used in other Ryobi hand tools of similar power. I highly recommend this rechargeable caulking gun and will purchase other Ryobi hand-tools that use the 18V lithium battery.